+run('fill 1 1 1 10 10 10 air') -> 123 // 123 block were filled, this operation was successful 123 times out of a possible 1000 blocks volume
+run('give @s stone 4') -> 1 // this operation was successful once
+
+
+### `save()`
+
+Performs autosave, saves all chunks, player data, etc. Useful for programs where autosave is disabled due to
+performance reasons and saves the world only on demand.
+
+### `load_app_data(), load_app_data(file)`
+
+Loads the app data associated with the app from the world /scripts folder. Without argument returns the memory
+managed and buffered / throttled NBT tag. With a file name - reads explicitly a file with that name from the
+scripts folder.
+
+You can use app data to save non-vanilla information separately from the world and other scripts.
+
+### `store_app_data(tag), store_app_data(tag, file)`
+
+Stores the app data associated with the app from the world /scripts folder. With the `file` parameter saves
+immediately and with every call, without `file` parameter, it may take up to 10 seconds for the output file
+to sync preventing flickering in case this tag changes frequently. It will be synced when server closes.
+
+### `tick_time()`
+
+Returns game tick counter. Can be used to run certain operations every n-th ticks, or to count in-game time
+
+### `game_tick(mstime?)`
+
+Causes game to run for one tick. By default runs it and returns control to the program, but can optionally
+accept expected tick length, in milliseconds. You can't use it to permanently change the game speed, but setting
+longer commands with custom tick speeds can be interrupted via `/script stop` command
+
++loop(1000,game_tick()) // runs the game as fast as it can for 1000 ticks +loop(1000,game_tick(100)) // runs the game twice as slow for 1000 ticks ++ +### `seed()` + +Returns current world seed. + +### `current_dimension()` + +Returns current dimension that the script runs in. + +### `in_dimension(smth, expr)` + +Evaluates the expression `expr` with different dimension execution context. `smth` can be an entity, +world-localized block, so not `block('stone')`, or a string representing a dimension like: + `'nether'`, `'the_nether'`, `'end'` or `'overworld'`, etc. + +### `schedule(delay, function, args...)` + +Schedules a user defined function to run with a specified `delay` ticks of delay. Scheduled functions run at the end +of the tick, and they will run in order they were scheduled. + +### `statistic(player, category, entry)` + +Queries in-game statistics for certain values. Categories include: + +* `mined`: blocks mined +* `crafted`: items crafted +* `used`: items used +* `broken`: items broken +* `picked_up`: items picked up +* `dropped`: items dropped +* `killed`: mobs killed +* `killed_by`: blocks mined +* `custom`: various random stats + +For the options of `entry`, consult your statistics page, or give it a guess. + +The call will return `null` if the statistics options are incorrect, or player didn't get these in their history. +If the player encountered the statistic, or game created for him empty one, it will return a number. +Scarpet will not affect the entries of the statistics, even if it is just creating empty ones. With `null` response +it could either mean your input is wrong, or statistic has effectively a value of `0`. + +### `plop(pos, what)` + +Plops a structure or a feature at a given `pos`, so block, triple position coordinates or a list of coordinates. +To `what` gets plopped and exactly where it often depends on the feature or structure itself. For example, all +structures are chunk aligned, and often span multiple chunks. Repeated calls to plop a structure in the same chunk +would result either in the same structure generated on top of each other, or with different state, but same position. +Most structures generate at specific altitudes, which are hardcoded, or with certain blocks around them. API will +cancel all extra position / biome / random requirements for structure / feature placement, but some hardcoded +limitations may still cause some of structures/features not to place. Some features require special blocks to be +present, like coral -> water or ice spikes -> snow block, and for some features, like fossils, placement is all sorts +of messed up. This can be partially avoided for structures by setting their structure information via `set_structure`, +which sets it without looking into world blocks, and then use `plop` to fill it with blocks. This may, or may not work. + +All generated structures will retain their properties, like mob spawning, however in many cases the world / dimension +itself has certain rules to spawn mobs, like plopping a nether fortress in the overworld will not spawn nether mobs, +because nether mobs can spawn only in the nether, but plopped in the nether - will behave like a valid nether fortress. + +`plop` will not use world random number generator to generate structures and features, but its own. This has a benefit +that they will generate properly randomly, not the same time every time. + +Structure list: + +* `monument`: Ocean Monument. Generates at fixed Y coordinate, surrounds itself with water. +* `fortress`: Nether Fortress. Altitude varies, but its bounded by the code. +* `mansion`: Woodland Mansion +* `jungle_temple`: Jungle Temple +* `desert_temple`: Desert Temple. Generates at fixed Y altitude. +* `end_city`: End City with Shulkers +* `igloo`: Igloo +* `shipwreck`: Shipwreck, version1? +* `shipwreck2`: Shipwreck, version2? +* `witch_hut` +* `ocean_ruin`, `ocean_ruin_small`, `ocean_ruin_tall`: Stone variants of ocean ruins. +* `ocean_ruin_warm`, `ocean_ruin_warm_small`, `ocean_ruin_warm_tall`: Sandstone variants of ocean ruins. +* `treasure`: A treasure chest. Yes, its a whole structure. +* `pillager_outpost`: A pillager outpost. +* `mineshaft`: A mineshaft. +* `mineshaft_mesa`: A Mesa (Badlands) version of a mineshaft. +* `village`: Plains, oak village. +* `village_desert`: Desert, sandstone village. +* `village_savanna`: Savanna, acacia village. +* `village_taiga`: Taiga, spruce village. +* `village_snowy`: Resolute, Canada. + +Feature list: + +* `oak` +* `oak_beehive`: oak with a hive (1.15+). +* `oak_large`: oak with branches. +* `oak_large_beehive`: oak with branches and a beehive (1.15+). +* `birch` +* `birch_large`: tall variant of birch tree. +* `shrub`: low bushes that grow in jungles. +* `shrub_acacia`: low bush but configured with acacia (1.14 only) +* `shrub_snowy`: low bush with white blocks (1.14 only) +* `jungle`: a tree +* `jungle_large`: 2x2 jungle tree +* `spruce` +* `spruce_large`: 2x2 spruce tree +* `pine`: spruce with minimal leafage (1.15+) +* `pine_large`: 2x2 spruce with minimal leafage (1.15+) +* `spruce_matchstick`: see 1.15 pine (1.14 only). +* `spruce_matchstick_large`: see 1.15 pine_large (1.14 only). +* `dark_oak` +* `acacia` +* `oak_swamp`: oak with more leaves and vines. +* `well`: desert well +* `grass`: a few spots of tall grass +* `grass_jungle`: little bushier grass feature (1.14 only) +* `lush_grass`: grass with patchy ferns (1.15+) +* `tall_grass`: 2-high grass patch (1.15+) +* `fern`: a few random 2-high ferns +* `cactus`: random cacti +* `dead_bush`: a few random dead bushi +* `fossils`: underground fossils, placement little wonky +* `mushroom_brown`: large brown mushroom. +* `mushroom_red`: large red mushroom. +* `ice_spike`: ice spike. Require snow block below to place. +* `glowstone`: glowstone cluster. Required netherrack above it. +* `melon`: a patch of melons +* `melon_pile`: a pile of melons (1.15+) +* `pumpkin`: a patch of pumpkins +* `pumpkin_pile`: a pile of pumpkins (1.15+) +* `sugarcane` +* `lilypad` +* `dungeon`: Dungeon. These are hard to place, and fail often. +* `iceberg`: Iceberg. Generate at sea level. +* `iceberg_blue`: Blue ice iceberg. +* `lake` +* `lava_lake` +* `end_island` +* `chorus`: Chorus plant. Require endstone to place. +* `sea_grass`: a patch of sea grass. Require water. +* `sea_grass_river`: a variant. +* `kelp` +* `coral_tree, coral_mushroom, coral_claw`: various coral types, random color. +* `coral`: random coral structure. Require water to spawn. +* `sea_pickle` +* `boulder`: A rocky, mossy formation from a giant taiga biome. Doesn't update client properly, needs relogging. diff --git a/docs/scarpet/api/BlockIterations.md b/docs/scarpet/api/BlockIterations.md new file mode 100644 index 00000000..304815cf --- /dev/null +++ b/docs/scarpet/api/BlockIterations.md @@ -0,0 +1,34 @@ +# Iterating over larger areas of blocks + +These functions help scan larger areas of blocks without using generic loop functions, like nested `loop`. + +### `scan(cx, cy, cz, dx, dy, dz, px?, py?, pz?, expr)` + +Evaluates expression over area of blocks defined by its center (`cx, cy, cz`), expanded in all directions +by `dx, dy, dz` blocks, or optionally in negative with `d` coords, and `p` coords in positive values. `expr` +receives `_x, _y, _z` as coords of current analyzed block and `_`, which represents the block itself. + +### `volume(x1, y1, z1, x2, y2, z2, expr)` + +Evaluates expression for each block in the area, the same as the `scan`function, but using two opposite corners of +the rectangular cuboid. Any corners can be specified, its like you would do with `/fill` command. + +### `neighbours(x, y, z), neighbours(block), neighbours(l(x,y,z))` + +Returns the list of 6 neighbouring blocks to the argument. Commonly used with other loop functions like `for`. + +
+for(neighbours(x,y,z),air(_)) => 4 // number of air blocks around a block ++ +### `rect(cx, cy, cz, dx?, dy?, dz?, px?, py?, pz?)` + +returns an iterator, just like `range` function that iterates over rectangular cubarea of blocks. If only center +point is specified, it iterates over 27 blocks. If `d` arguments are specified, expands selection of respective +number of blocks in each direction. If `p` arguments are specified, it uses `d` for negative offset, and `p` for positive. + +### `diamond(cx, cy, cz, radius?, height?)` + +Iterates over a diamond like area of blocks. With no radius and height, its 7 blocks centered around the middle +(block + neighbours). With a radius specified, it expands shape on x and z coords, and with a custom height, on y. +Any of these can be zero as well. radius of 0 makes a stick, height of 0 makes a diamond shape pad. diff --git a/docs/scarpet/api/BlocksAndWorldAccess.md b/docs/scarpet/api/BlocksAndWorldAccess.md new file mode 100644 index 00000000..99b48fe7 --- /dev/null +++ b/docs/scarpet/api/BlocksAndWorldAccess.md @@ -0,0 +1,530 @@ +# Blocks / World API + +## Specifying blocks + +### `block(x, y, z)`, `block(l(x,y,z))`, `block(state)` + +Returns either a block from specified location, or block with a specific state (as used by `/setblock` command), +so allowing for block properties, block entity data etc. Blocks otherwise can be referenced everywhere by its simple +string name, but its only used in its default state. + +
+block('air') => air
+block('iron_trapdoor[half=top]') => iron_trapdoor
+block(0,0,0) == block('bedrock') => 1
+block('hopper[facing=north]{Items:[{Slot:1b,id:"minecraft:slime_ball",Count:16b}]}') => hopper
+
+
+Retrieving a block with `block` function has also a side-effect of evaluating its current state and data.
+So if you use it later it will reflect block state and data of the block that was when block was called, rather than
+when it was used. Block values passed in various places like `scan` functions, etc, are not fully evaluated unless
+its properties are needed. This means that if the block at the location changes before its queried in the program this
+might result in getting the later state, which might not be desired. Consider the following example:
+
+set(10,10,10,'stone'); +scan(10,10,10,0,0,0, b = _); +set(10,10,10,'air'); +print(b); // 'air', block was remembered 'lazily', and evaluated by `print`, when it was already set to air +set(10,10,10,'stone'); +scan(10,10,10,0,0,0, b = block(_)); +set(10,10,10,'air'); +print(b); // 'stone', block was evaluated 'eagerly' but call to `block` ++ +## World Manipulation + +All the functions below can be used with block value, queried with coord triple, or 3-long list. All `pos` in the +functions referenced below refer to either method of passing block position. + +### `set(pos, block, property?, value?, ...)` + +First part of the `set` function is either a coord triple, list of three numbers, or other block with coordinates. +Second part, `block` is either block value as a result of `block()` function string value indicating the block name, +and optional `property - value` pairs for extra block properties. If `block` is specified only by name, then if a +destination block is the same the `set` operation is skipped, otherwise is executed, for other potential extra +properties. + +The returned value is either the block state that has been set, or `false` if block setting was skipped + +
+set(0,5,0,'bedrock') => bedrock
+set(l(0,5,0), 'bedrock') => bedrock
+set(block(0,5,0), 'bedrock') => bedrock
+scan(0,5,0,0,0,0,set(_,'bedrock')) => 1
+set(pos(players()), 'bedrock') => bedrock
+set(0,0,0,'bedrock') => 0 // or 1 in overworlds generated in 1.8 and before
+scan(0,100,0,20,20,20,set(_,'glass'))
+ // filling the area with glass
+scan(0,100,0,20,20,20,set(_,block('glass')))
+ // little bit faster due to internal caching of block state selectors
+b = block('glass'); scan(0,100,0,20,20,20,set(_,b))
+ // yet another option, skips all parsing
+set(x,y,z,'iron_trapdoor') // sets bottom iron trapdoor
+set(x,y,z,'iron_trapdoor[half=top]') // Incorrect. sets bottom iron trapdoor - no parsing of properties
+set(x,y,z,'iron_trapdoor','half','top') // correct - top trapdoor
+set(x,y,z, block('iron_trapdoor[half=top]')) // also correct, block() provides extra parsing
+set(x,y,z,'hopper[facing=north]{Items:[{Slot:1b,id:"minecraft:slime_ball",Count:16b}]}') // extra block data
+
+
+### `without_updates(expr)`
+
+Evaluates subexpression without causing updates when blocks change in the world
+
+Consider following scenario: We would like to generate a bunch of terrain in a flat world following a perling noise
+generator. The following code causes cascading effect as blocks placed on chunk borders will cause other chunks to get
+loaded to full, thus generated:
+
+
+__config() -> m(l('scope', 'global'));
+__on_chunk_generated(x, z) -> (
+ scan(x,0,z,0,0,0,15,15,15,
+ if (perlin(_x/16, _y/8, _z/16) > _y/16,
+ set(_, 'black_stained_glass');
+ )
+ )
+)
+
+
+The following addition resolves this issue, by not allowing block updates pass chunk borders:
+
+
+__config() -> m(l('scope', 'global'));
+__on_chunk_generated(x, z) -> (
+ without_updates(
+ scan(x,0,z,0,0,0,15,15,15,
+ if (perlin(_x/16, _y/8, _z/16) > _y/16,
+ set(_, 'black_stained_glass');
+ )
+ )
+ )
+)
+
+
+### `place_item(item, pos, facing?, sneak?)`
+
+Places a given item in the world like it was placed by a player. Item names are default minecraft item name,
+less the minecraft prefix. Default facing is 'up', but there are other options: 'down', 'north', 'east', 'south',
+'west', but also there are other secondary directions important for placement of blocks like stairs, doors, etc.
+Try experiment with options like 'north-up' which is placed facing north with cursor pointing to the upper part of the
+block, or 'up-north', which means a block placed facing up (player looking down) and placed smidge away of the block
+center towards north. Optional sneak is a boolean indicating if a player would be sneaking while placing the
+block - this option only affects placement of chests and scaffolding at the moment. Returns true if placement was
+successful, false otherwise.
+
+
+place_item('stone',x,y,z) // places a stone block on x,y,z block
+place_item('piston,x,y,z,'down') // places a piston facing down
+place_item('carrot',x,y,z) // attempts to plant a carrot plant. Returns true if could place carrots at that position.
+
+
+### `set_poi(pos, type, occupancy?)`
+
+Sets a Point of Interest (POI) of a specified type with optional custom occupancy. By default new POIs are not occupied.
+If type is `null`, POI at position is removed. In any case, previous POI is also removed. Available POI types are:
+
+* `'unemployed', 'armorer', 'butcher', 'cartographer', 'cleric', 'farmer', 'fisherman', 'fletcher', 'leatherworker', 'librarian', 'mason', 'nitwit', 'shepherd', 'toolsmith', 'weaponsmith', 'home', 'meeting', 'beehive', 'bee_nest', 'nether_portal'`
+
+Interestingly, `unemployed`, and `nitwit` are not used in the game, meaning, they could be used as permanent spatial
+markers for scarpet apps. `meeting` is the only one with increased max occupancy of 32.
+
+### `set_biome(pos, biome_name)`
+
+changes biome at that block position.
+
+### `update(pos)`
+
+Causes a block update at position.
+
+### `block_tick(pos)`
+
+Causes a block to tick at position.
+
+### `random_tick(pos)`
+
+Causes a random tick at position.
+
+### `destroy(pos), destroy(pos, -1), destroy(pos,
+mine(x,y,z) ->
+(
+ p = player();
+ slot = p~'selected_slot';
+ item_tuple = inventory_get(p, slot);
+ if (!item_tuple, destroy(x,y,z,'air'); return()); // empty hand, just break with 'air'
+ l(item, count, tag) = item_tuple;
+ tag_back = destroy(x,y,z, item, tag);
+ if (tag_back == false, // failed to break the item
+ return(tag_back)
+ );
+ if (tag_back == true, // block broke, tool has no tag
+ return(tag_back)
+ );
+ if (tag_back == null, //item broke
+ delete(tag:'Damage');
+ inventory_set(p, slot, count-1, item, tag);
+ return(tag_back)
+ );
+ if (type(tag_back) == 'nbt', // item didn't break, here is the effective nbt
+ inventory_set(p, slot, count, item, tag_back);
+ return(tag_back)
+ );
+ print('How did we get here?');
+)
+
+
+### `harvest(player, pos)`
+
+Causes a block to be harvested by a specified player entity. Honors player item enchantments, as well as damages the
+tool if applicable. If the entity is not a valid player, no block gets destroyed. If a player is not allowed to break
+that block, a block doesn't get destroyed either.
+
+## Block and World querying
+
+### `pos(block), pos(entity)`
+
+Returns a triple of coordinates of a specified block or entity. Technically entities are queried with `query` function
+and the same can be achieved with `query(entity,'pos')`, but for simplicity `pos` allows to pass all positional objects.
+
+
+pos(block(0,5,0)) => l(0,5,0)
+pos(players()) => l(12.3, 45.6, 32.05)
+pos(block('stone')) => Error: Cannot fetch position of an unrealized block
+
+
+### `pos_offset(pos, direction, amount?)`
+
+Returns a coords triple that is offset in a specified `direction` by `amount` of blocks. The default offset amount is
+1 block. To offset into opposite facing, use negative numbers for the `amount`.
+
++pos_offset(block(0,5,0), 'up', 2) => l(0,7,0) +pos_offset(l(0,5,0), 'up', -2 ) => l(0,3,0) ++ +### `block_properties(pos)` + +Returns a list of available block properties for a particular block. If a block has no properties, returns an empty list. + +### `property(pos, name)` + +Returns property of block at `pos`, or specified by `block` argument. If a block doesn't have that property, `null` +value is returned. Returned values are always strings. It is expected from the user to know what to expect and convert +values to numbers using `number()` function or booleans using `bool()` function. + +
+set(x,y,z,'iron_trapdoor','half','top'); property(x,y,z,'half') => top
+set(x,y,z,'air'); property(x,y,z,'half') => null
+property(block('iron_trapdoor[half=top]'),'half') => top
+property(block('iron_trapdoor[half=top]'),'powered') => false
+bool(property(block('iron_trapdoor[half=top]'),'powered')) => 0
+
+
+### `block_data(pos)`
+
+Return NBT string associated with specific location, or null if the block does not carry block data. Can be currently
+used to match specific information from it, or use it to copy to another block
+
+ block_data(x,y,z) => '{TransferCooldown:0,x:450,y:68, ... }'
+
+
+### `poi(pos), poi(pos, radius), poi(pos, radius, status)`
+
+Queries a POI (Point of Interest) at a given position, returning `null` if none is found, or tuple of poi type and its
+occupancy load. With optional `radius` and `status`, returns a list of POIs around `pos` within a given `radius`.
+If `status` is specified (either 'available', or 'occupied') returns only POIs with that status. The return format is
+again, poi type, occupancy load, and extra tripple of coordinates.
+
+Querying for POIs using the radius is intended use of POI mechanics and ability of accessing individual POIs
+via `poi(pos)` in only provided for completness.
+
++poi(x,y,z) => null // nothing set at position +poi(x,y,z) => ['meeting',3] // its a bell-type meeting point occupied by 3 villagers +poi(x,y,z,5) => [] // nothing around +poi(x,y,z,5) => [['nether_portal',0,[7,8,9]],['nether_portal',0,[7,9,9]]] // two portal blocks in the range ++ +### `biome(pos)` + +returns biome at that block position. + +### `solid(pos)` + +Boolean function, true if the block is solid + +### `air(pos)` + +Boolean function, true if a block is air.... or cave air... or void air.... or any other air they come up with. + +### `liquid(pos)` + +Boolean function, true if the block is liquid, or liquidlogged + +### `flammable(pos)` + +Boolean function, true if the block is flammable + +### `transparent(pos)` + +Boolean function, true if the block is transparent + +### `opacity(pos)` + +Numeric, returning opacity level of a block + +### `blocks_daylight(pos)` + +Boolean function, true if the block blocks daylight + +### `emitted_light(pos)` + +Numeric, returning light level emitted from block + +### `light(pos)` + +Integer function, returning total light level at position + +### `block_light(pos)` + +Integer function, returning block light at position. From torches and other light sources. + +### `sky_light(pos)` + +Numeric function, returning sky light at position. From the sky access. + +### `see_sky(pos)` + +Boolean function, returning true if the block can see sky. + +### `hardness(pos)` + +Numeric function, indicating hardness of a block. + +### `blast_resistance(pos)` + +Numeric function, indicating blast_resistance of a block. + +### `in_slime_chunk(pos)` + +Boolean indicating if the given block position is in a slime chunk. + +### `top(type, pos)` + +Returns the Y value of the topmost block at given x, z coords (y value of a block is not important), according to the +heightmap specified by `type`. Valid options are: + +* `light`: topmost light blocking block (1.13 only) +* `motion`: topmost motion blocking block +* `terrain`: topmost motion blocking block except leaves +* `ocean_floor`: topmost non-water block +* `surface`: topmost surface block + +
+top('motion', x, y, z) => 63
+top('ocean_floor', x, y, z) => 41
+
+
+### `loaded(pos)`
+
+Boolean function, true if the block is accessible for the game mechanics. Normally `scarpet` doesn't check if operates
+on loaded area - the game will automatically load missing blocks. We see this as advantage. Vanilla `fill/clone`
+commands only check the specified corners for loadness.
+
+To check if block is truly loaded, I mean in memory, use `generation_status(x) != null`, as chunks can still be loaded
+outside of the playable area, just are not used any of the game mechanics processes.
+
++loaded(pos(players())) => 1 +loaded(100000,100,1000000) => 0 ++ +### `(Deprecated) loaded_ep(pos)` + +Boolean function, true if the block is loaded and entity processing, as per 1.13.2 + +Deprecated as of scarpet 1.6, use `loaded_status(x) > 0`, or just `loaded(x)` with the same effect + +### `loaded_status(pos)` + +Returns loaded status as per new 1.14 chunk ticket system, 0 for inaccessible, 1 for border chunk, 2 for ticking, +3 for entity ticking + +### `generation_status(pos), generation_status(pos, true)` + +Returns generation status as per new 1.14 chunk ticket system. Can return any value from several available but chunks +can only be valid in a few states: `full`, `features`, `liquid_carvers`, and `structure_starts`. Returns `null` +if the chunk is not in memory unless called with optional `true`. + +### `structures(pos), structures(pos, structure_name)` + +Returns structure information for a given block position. Note that structure information is the same for all the +blocks from the same chunk. `structures` function can be called with a block, or a block and a structure name. In +the first case it returns a map of structures at a given position, keyed by structure name, with values indicating +the bounding box of the structure - a pair of two 3-value coords (see examples). When called with an extra structure +name, returns list of components for that structure, with their name, direction and two sets of coordinates +indicating the bounding box of the structure piece. + +### `structure_references(pos), structure_references(pos, structure_name)` + +Returns structure information that a chunk with a given block position is part of. `structure_references` function +can be called with a block, or a block and a structure name. In the first case it returns a list of structure names +that give chunk belongs to. When called with an extra structure name, returns list of positions pointing to the +lowest block position in chunks that hold structure starts for these structures. You can query that chunk structures +then to get its bounding boxes. + +### `set_structure(pos, structure_name), set_structure(pos, structure_name, null)` + +Creates or removes structure information of a structure associated with a chunk of `pos`. Unlike `plop`, blocks are +not placed in the world, only structure information is set. For the game this is a fully functional structure even +if blocks are not set. To remove structure a given point is in, use `structure_references` to find where current +structure starts. + +### `suffocates(pos)` + +Boolean function, true if the block causes suffocation. + +### `power(pos)` + +Numeric function, returning redstone power level at position. + +### `ticks_randomly(pos)` + +Boolean function, true if the block ticks randomly. + +### `blocks_movement(pos)` + +Boolean function, true if block at position blocks movement. + +### `block_sound(pos)` + +Returns the name of sound type made by the block at position. One of: + +* `wood` +* `gravel` +* `grass` +* `stone` +* `metal` +* `glass` +* `wool` +* `sand` +* `snow` +* `ladder` +* `anvil` +* `slime` +* `sea_grass` +* `coral` + +### `material(pos)` + +Returns the name of material of the block at position. very useful to target a group of blocks. One of: + +* `air` +* `void` +* `portal` +* `carpet` +* `plant` +* `water_plant` +* `vine` +* `sea_grass` +* `water` +* `bubble_column` +* `lava` +* `snow_layer` +* `fire` +* `redstone_bits` +* `cobweb` +* `redstone_lamp` +* `clay` +* `dirt` +* `grass` +* `packed_ice` +* `sand` +* `sponge` +* `wood` +* `wool` +* `tnt` +* `leaves` +* `glass` +* `ice` +* `cactus` +* `stone` +* `iron` +* `snow` +* `anvil` +* `barrier` +* `piston` +* `coral` +* `gourd` +* `dragon_egg` +* `cake` + +### `map_colour(pos)` + +Returns the map colour of a block at position. One of: + +* `air` +* `grass` +* `sand` +* `wool` +* `tnt` +* `ice` +* `iron` +* `foliage` +* `snow` +* `clay` +* `dirt` +* `stone` +* `water` +* `wood` +* `quartz` +* `adobe` +* `magenta` +* `light_blue` +* `yellow` +* `lime` +* `pink` +* `gray` +* `light_gray` +* `cyan` +* `purple` +* `blue` +* `brown` +* `green` +* `red` +* `black` +* `gold` +* `diamond` +* `lapis` +* `emerald` +* `obsidian` +* `netherrack` +* `white_terracotta` +* `orange_terracotta` +* `magenta_terracotta` +* `light_blue_terracotta` +* `yellow_terracotta` +* `lime_terracotta` +* `pink_terracotta` +* `gray_terracotta` +* `light_gray_terracotta` +* `cyan_terracotta` +* `purple_terracotta` +* `blue_terracotta` +* `brown_terracotta` +* `green_terracotta` +* `red_terracotta` +* `black_terracotta` diff --git a/docs/scarpet/api/Entities.md b/docs/scarpet/api/Entities.md new file mode 100644 index 00000000..921b9e89 --- /dev/null +++ b/docs/scarpet/api/Entities.md @@ -0,0 +1,471 @@ +# Entity API + +## Entity Selection + +Entities have to be fetched before using them. Entities can also change their state between calls to the script if +game happens either in between separate calls to the programs, or if the program calls `game_tick` on its own. +In this case - entities would need to be re-fetched, or the code should account for entities getting dead. + +### `player(), player(type), player(name)` + +With no arguments, it returns the calling player or the player closest to the caller. Note that the main context +will receive `p` variable pointing to this player. With `type` or `name` specified it will try first to match a type, +returning a list of players matching a type, and if this fails, will assume its player name query retuning player with +that name, or `null` if no player was found. With `'all'`, list of all players in the game, in all dimensions, so end +user needs to be cautious, that you might be referring to wrong blocks and entities around the player in question. +With `type = '*'` it returns all players in caller dimension, `'survival'` returns all survival and adventure players, +`'creative'` returns all creative players, `'spectating'` returns all spectating players, and `'!spectating'`, +all not-spectating players. If all fails, with `name`, the player in question, if is logged in. + +### `entity_id(uuid), entity_id(id)` + +Fetching entities wither by their ID obtained via `entity ~ 'id'`, which is unique for a dimension and current world +run, or by UUID, obtained via `entity ~ 'uuid'`. It returns null if no such entity is found. Safer way to 'store' +entities between calls, as missing entities will be returning `null`. Both calls using UUID or numerical ID are `O(1)`, +but obviously using UUIDs takes more memory and compute. + +### `entity_list(type)` + +Returns global lists of entities in the current dimension of a specified type. Currently the following +selectors are available: + +* `*`: all entites +* `living` +* `items` +* `players` +* `!players` + +### `entity_area(type, cx, cy, cz, dx, dy, dz)` + +Returns entities of a specified type in an area centered on `cx, cy, cz` and at most `dx, dy, dz` blocks away from +the center point. Uses same selectors as `entities_list` + +### `entity_selector(selector)` + +Returns entities satisfying given vanilla entity selector. Most complex among all the methods of selecting entities, +but the most capable. Selectors are cached so should be as fast as other methods of selecting entities. + +### `spawn(name, pos, nbt?)` + +Spawns and places an entity in world, like `/summon` vanilla command. Requires a position to spawn, and optional +extra nbt data to merge with the entity. What makes it different from calling `run('summon ...')`, is the fact that +you get the entity back as a return value, which is swell. + +## Entity Manipulation + +Unlike with blocks, that use plethora of vastly different querying functions, entities are queried with `query` +function and altered via `modify` function. Type of information needed or values to be modified are different for +each call. + +Using `~` (in) operator is an alias for `query`. Especially useful if a statement has no arguments, +which in this case can be radically simplified + +
+query(p, 'name') <=> p ~ 'name' // much shorter and cleaner
+query(p, 'holds', 'offhand') <=> p ~ l('holds', 'offhand') // not really but can be done
+
+
+### `query(e,'removed')`
+
+Boolean. True if the entity is removed
+
+### `query(e,'id')`
+
+Returns numerical id of the entity. Most efficient way to keep track of entites in a script.
+Ids are only unique within current game session (ids are not preserved between restarts),
+and dimension (each dimension has its own ids which can overlap.
+
+### `query(e,'uuid')`
+
+Returns UUID (unique id) of the entity. Can be used to access entities with the other vanilla commands and
+remains unique regardless of the dimension, and is preserved between game restarts. Apparently players cannot be
+accessed via UUID, but name instead.
+
+
+map(entities_area('*',x,y,z,30,30,30),run('kill '+query(_,'id'))) // doesn't kill the player
+
+
+### `query(e,'pos')`
+
+Triple of entity position
+
+### `query(e,'location')`
+
+Quin-tuple of entity position (x, y, and z coords), and rotation (yaw, pitch)
+
+### `query(e,'x'), query(e,'y'), query(e,'z')`
+
+Respective entity coordinate
+
+### `query(e,'pitch'), query(e,'yaw')`
+
+Pitch and Yaw or where entity is looking.
+
+### `query(e,'look')`
+
+Returns a 3d vector where the entity is looking.
+
+### `query(e,'motion')`
+
+Triple of entity motion vector, `l(motion_x, motion_y, motion_z)`
+
+### `query(e,'motion_x'), query(e,'motion_y'), query(e,'motion_z')`
+
+Respective component of the motion vector
+
+### `query(e,'name'), query(e,'custom_name'), query(e,'type')`
+
+String of entity name
+
+query(e,'name') => Leatherworker +query(e,'custom_name') => null +query(e,'type') => villager ++ +### `query(e,'is_riding')` + +Boolean. True if riding another entity. + +### `query(e,'is_ridden')` + +Boolean. True if another entity is riding it. + +### `query(e,'passengers')` + +List of entities riding the entity. + +### `query(e,'mount')` + +Entity that `e` rides. + +### `query(e,'tags')` + +List of entity tags. + +### `query(e,'has_tags',tag)` + +Boolean, True if the entity is marked with `tag`. + +### `query(e,'is_burning')` + +Boolean, True if the entity is burning. + +### `query(e,'fire')` + +Number of remaining ticks of being on fire. + +### `query(e,'silent')` + +Boolean, True if the entity is silent. + +### `query(e,'gravity')` + +Boolean, True if the entity is affected by gravity, like most entities do. + +### `query(e,'immune_to_fire')` + +Boolean, True if the entity is immune to fire. + +### `query(e,'dimension')` + +Name of the dimension entity is in. + +### `query(e,'height')` + +Height of the entity. + +### `query(e,'width')` + +Width of the entity. + +### `query(e,'eye_height')` + +Eye height of the entity. + +### `query(e,'age')` + +Age, in ticks, of the entity, i.e. how long it existed. + +### `query(e,'breeding_age')` + +Breeding age of passive entity, in ticks. If negative it it time to adulthood, if positive, breeding cooldown + +### `query(e,'despawn_timer')` + +For living entities - the number of ticks they fall outside of immediate player presence. + +### `query(e,'item')` + +The item triple (name, count, nbt) if its an item entity, `null` otherwise + +### `query(e,'count')` + +Number of items in a stack from item entity, `null` otherwise + +### `query(e,'pickup_delay')` + +Retrieves pickup delay timeout for an item entity, `null` otherwise + +### `query(e,'is_baby')` + +Boolean, true if its a baby. + +### `query(e,'target')` + +Returns mob's attack target or null if none or not applicable. + +### `query(e,'home')` + +Returns creature's home position or null if none or not applicable. + +### `query(e,'sneaking')` + +Boolean, true if entity is sneaking. + +### `query(e,'sprinting')` + +Boolean, true if entity is sprinting. + +### `query(e,'swimming')` + +Boolean, true if entity is swimming. + +### `query(e,'jumping')` + +Boolean, true if entity is jumping. + +### `query(e,'gamemode')` + +String with gamemode, or `null` if not a player. + +### `query(e,'gamemode_id')` + +Good'ol gamemode id, or null if not a player. + +### `query(e,'player_type')` + +Returns `null` if the argument is not a player, otherwise: + +* `singleplayer`: for singleplayer game +* `multiplayer`: for players on a dedicated server +* `lan_host`: for singleplayer owner that opened the game to LAN +* `lan_player`: for all other players that connected to a LAN host +* `fake`: any carpet-spanwed fake player +* `shadow`: any carpet-shadowed real player +* `realms`: ? + +### `query(e,'permission_level')` + +Player's permission level, or `null` if not applicable for this entity. + +### `query(e,'effect',name?)` + +Without extra arguments, it returns list of effect active on a living entity. Each entry is a triple of short +effect name, amplifier, and remaining duration. With an argument, if the living entity has not that potion active, +returns `null`, otherwise return a tuple of amplifier and remaining duration. + +
+query(p,'effect') => [[haste, 0, 177], [speed, 0, 177]] +query(p,'effect','haste') => [0, 177] +query(p,'effect','resistance') => null ++ +### `query(e,'health')` + +Number indicating remaining entity health, or `null` if not applicable. + +### `query(e,'holds',slot?)` + +Returns triple of short name, stack count, and NBT of item held in `slot`. Available options for `slot` are: + +* `mainhand` +* `offhand` +* `head` +* `chest` +* `legs` +* `feet` + +If `slot` is not specified, it defaults to the main hand. + +### `query(e,'selected_slot')` + +Number indicating the selected slot of entity inventory. Currently only applicable to players. + +### `query(e,'facing', order?)` + +Returns where the entity is facing. optional order (number from 0 to 5, and negative), indicating primary directions +where entity is looking at. From most prominent (order 0) to opposite (order 5, or -1) + +### `query(e,'trace', reach?, options?...)` + +Returns the result of ray tracing from entity perspective, indicating what it is looking at. Default reach is 4.5 +blocks (5 for creative players), and by default it traces for blocks and entities, identical to player attack tracing +action. This can be customized with `options`, use 'blocks' to trace for blocks, 'liquids' to include liquid blocks +as possible results, and 'entities' to trace entities. Any combination of the above is possible. When tracing +entities and blocks, blocks will take over the priority even if transparent or non-colliding +(aka fighting chickens in tall grass). + +Regardless of the options selected, the result could be `null` if nothing is in reach, entity, if look targets an +entity, and block value if block is in reach. + +### `query(e,'nbt',path?)` + +Returns full NBT of the entity. If path is specified, it fetches only that portion of the NBT, that corresponds to the +path. For specification of `path` attribute, consult vanilla `/data get entity` command. + +Note that calls to `nbt` are considerably more expensive comparing to other calls in Minecraft API, and should only +be used when there is no other option. Returned value is of type `nbt`, which can be further manipulated with nbt +type objects via `get, put, has, delete`, so try to use API calls first for that. + +## Entity Modification + +Like with entity querying, entity modifications happen through one function. Most position and movements modifications +don't work currently on players as their position is controlled by clients. + +Currently there is no ability to modify NBT directly, but you could always use `run('data modify entity` + +### `modify(e,'remove')` + +Removes (not kills) entity from the game. + +### `modify(e,'kill')` + +Kills the entity. + +### `modify(e, 'pos', x, y, z), modify(e, 'pos', l(x,y,z) )` + +Moves the entity to a specified coords. + +### `modify(e, 'location', x, y, z, yaw, pitch), modify(e, 'location', l(x, y, z, yaw, pitch) )` + +Changes full location vector all at once. + +### `modify(e, 'x', x), modify(e, 'y', y), modify(e, 'z', z)` + +Moves the entity in.... one direction. + +### `modify(e, 'pitch', pitch), modify(e, 'yaw', yaw)` + +Changes entity's pitch or yaw. + +### `modify(e, 'move', x, y, z), modify(e, 'move', l(x,y,z) )` + +Moves the entity by a vector from its current location. + +### `modify(e, 'motion', x, y, z), modify(e, 'motion', l(x,y,z) )` + +Sets the motion vector (where and how much entity is moving). + +### `modify(e, 'motion_z', x), modify(e, 'motion_y', y), modify(e, 'motion_z', z)` + +Sets the corresponding component of the motion vector. + +### `modify(e, 'accelerate', x, y, z), modify(e, 'accelerate', l(x, y, z) )` + +Adds a vector to the motion vector. Most realistic way to apply a force to an entity. + +### `modify(e, 'custom_name'), modify(e, 'custom_name', name )` + +### `modify(e, 'age', number)` + +Modifies entity's internal age counter. Fiddling with this will affect directly behaviours of complex +entities, so use it with caution. + +### `modify(e, 'pickup_delay', number)` + +### `modify(e, 'breeding_age', number)` + +### `modify(e, 'despawn_timer', number)` + +Sets a custom despawn timer value. + +### `modify(e, 'dismount')` + +Dismounts riding entity. + +### `modify(e, 'mount', other)` + +Mounts the entity to the `other`. + +### `modify(e, 'drop_passengers')` + +Shakes off all passengers. + +### `modify(e, 'mount_passengers', passenger, ? ...), modify(e, 'mount_passengers', l(passengers) )` + +Mounts on all listed entities on `e`. + +### `modify(e, 'tag', tag, ? ...), modify(e, 'tag', l(tags) )` + +Adds tag / tags to the entity. + +### `modify(e, 'clear_tag', tag, ? ...), modify(e, 'clear_tag', l(tags) )` + +Removes tag from entity. + +### `modify(e, 'talk')` + +Make noises. + +### `modify(e, 'ai', boolean)` + +If called with `false` value, it will disable AI in the mob. `true` will enable it again. + +### `modify(e, 'no_clip', boolean)` + +Sets if the entity obeys any collisions, including collisions with the terrain and basic physics. Not affecting +players, since they are controlled client side + +### `modify(e, 'effect', name, duration?, amplifier?, show_particles?, show_icon?)` + +Applies status effect to the living entity. Takes several optional parameters, which default to `0`, `true` +and `true`. If no duration is specified, or it is null or 0, the effect is removed. + +### `modify(e, 'home', null), modify(e, 'home', block, distance?), modify(e, 'home', x, y, z, distance?)` + +Sets AI to stay around the home position, within `distance` blocks from it. `distance` defaults to 16 blocks. +`null` removes it. _May_ not work fully with mobs that have this AI built in, like Villagers. + +## Entity Events + +There is a number of events that happen to entities that you can attach your own code to in the form of event handlers. +The event handler is any function that runs in your package that accepts certain expected parameters, which you can +expand with your own arguments. When it comes to the moment when the given command needs to be executed, it does so +providing that number of arguments it accepts is equal number of event arguments, and extra arguments passed when +defining the callback with `entity_event` + +The following events can be handled by entities. + +* `'on_tick'`: executes every tick right before entity is ticked in the game. Required arguments: `entity` +* `'on_death'`: executes once when a living entity dies. Required arguments: `entity, reason` +* `'on_removed'`: execute once when an entity is removed. Required arguments: `entity` +* `'on_damaged'`: executed every time a living entity is about to receive damage. +Required arguments: `entity, amount, source, attacking_entity` + +It doesn't mean that all entity types will have a chance to execute a given event, but entities will not error +when you will attach inapplicable event to it. + +### `entity_event(e, event, call_name, args...)` + +Attaches specific function from the current package to be called upon the `event`, with extra `args` curried to the +original required arguments for the event handler + +
+protect_villager(entity, amount, source, source_entity, healing_player) ->
+(
+ if(source_entity && source_entity~'type' != 'player',
+ modify(entity, 'health', amount + entity~'health' );
+ particle('end_rod', pos(entity)+l(0,3,0));
+ print(str('%s healed thanks to %s', entity, healing_player))
+ )
+);
+__on_player_interacts_with_entity(player, entity, hand) ->
+(
+ if (entity~'type' == 'villager',
+ entity_event(entity, 'on_damage', 'protect_villager', player~'name')
+ )
+)
+
+
+In this case this will protect a villager from entity damage (zombies, etc.) except players by granting all the
+health back to the villager after being harmed.
diff --git a/docs/scarpet/api/Events.md b/docs/scarpet/api/Events.md
new file mode 100644
index 00000000..5df38a5b
--- /dev/null
+++ b/docs/scarpet/api/Events.md
@@ -0,0 +1,52 @@
+# Scarpet events system
+
+Provides the ability to execute specific function whenever an event occurs. The functions to be registered need to
+conform with the arguments to the event specification. When loading module functions, each function that starts
+with `__on_...` and has the required arguments, will be bound automatically. In case of player specific modules,
+all player action events will be directed to the appropriate player space, and all tick events will be executed in
+the global context, so its not a good idea to mix these two, so use either of these, or use commands to call tick
+events directly, or handle player specific data inside a module. In near future using global events
+(on_tick, on_chunk_generated) will be not allowed in player scoped apps.
+
+### Event list
+
+Here is a list of events that can be handled by scarpet. This list includes prefixes required by modules to autoload
+them, but you can add any function to any event if it accepts required number of parameters:
+
++__on_tick() // can access blocks and entities in the overworld +__on_tick_nether() // can access blocks and entities in the nether +__on_tick_ender() // can access blocks and entities in the end +__on_chunk_generated(x,z) // called after a chunk is promoted to the full chunk, + // prodiving lowest x and z coords in the chunk + // event will not work with optifine installed in the game +// player specific callbacks +__on_player_uses_item(player, item_tuple, hand) // right click action +__on_player_releases_item(player, item_tuple, hand) // client action (e.g. bow) +__on_player_finishes_using_item(player, item_tuple, hand)) // server action (e.g. food), called item is from before it is used. +__on_player_clicks_block(player, block, face) // left click attack on a block +__on_player_breaks_block(player, block) // called after block is broken (the caller receives previous blockstate) +__on_player_right_clicks_block(player, item_tuple, hand, block, face, hitvec) // player right clicks block with anything +__on_player_interacts_with_block(player, hand, block, face, hitvec) //right click on a block resulted in activation of said block +__on_player_places_block(player, item_tuple, hand, block) // player have just placed the block. +__on_player_interacts_with_entity(player, entity, hand) +__on_player_attacks_entity(player, entity) +__on_player_rides(player, forward, strafe, jumping, sneaking) +__on_player_jumps(player) +__on_player_deploys_elytra(player) +__on_player_wakes_up(player) +__on_player_starts_sneaking(player) +__on_player_stops_sneaking(player) +__on_player_starts_sprinting(player) +__on_player_stops_sprinting(player) +__on_player_drops_item(player) +__on_player_drops_stack(player) +__on_statistic(player, category, event, value) // player statistic changes ++ +### `/script event` command + +used to display current events and bounded functions. use `add_to` ro register new event, or `remove_from` to +unbind a specific function from an event. Function to be bounded to an event needs to have the same number of +parameters as the action is attempting to bind to (see list above). All calls in modules loaded via `/script load` +that have functions listed above will be automatically bounded and unbounded when script is unloaded. diff --git a/docs/scarpet/api/Inventories.md b/docs/scarpet/api/Inventories.md new file mode 100644 index 00000000..972cf5b5 --- /dev/null +++ b/docs/scarpet/api/Inventories.md @@ -0,0 +1,116 @@ +# Inventory and Items API + +## Manipulating inventories of blocks and entities + +Most functions in this category require inventory as the first argument. Inventory could be specified by an entity, +or a block, or position (three coordinates) of a potential block with inventory. Player enderchest inventory require +two arguments, keyword `'enderchest'`, followed by the player entity argument. If the entity or a block doesn't have +an inventory, they typically do nothing and return null. + +Most items returned are in the form of a triple of item name, count, and nbt or the extra data associated with an item. +Manipulating of the nbt data can be costly, but retrieving them from the tuple to match other aspects is cheap + +### `stack_limit(item)` + +Returns number indicating what is the stack limit for the item. Its typically 1 (non-stackable), 16 (like buckets), +or 64 - rest. It is recommended to consult this, as other inventory API functions ignore normal stack limits, and +it is up to the programmer to keep it at bay. As of 1.13, game checks for negative numbers and setting an item to +negative is the same as empty. + +
+stack_limit('wooden_axe') => 1
+stack_limit('ender_pearl') => 16
+stack_limit('stone') => 64
+
+
+### `item_category(item)`
+
+Returns the string representing the category of a given item, like `building_blocks`, `combat`, or `tools`.
+
+
+item_category('wooden_axe') => tools
+item_category('ender_pearl') => misc
+item_category('stone') => building_blocks
+
+
+### `inventory_size(inventory)`
+
+Returns the size of the inventory for the entity or block in question. Returns null if the block or entity don't
+have an inventory
+
+
+inventory_size(player()) => 41
+inventory_size('enderchest', player()) => 27 // enderchest
+inventory_size(x,y,z) => 27 // chest
+inventory_size(block(pos)) => 5 // hopper
+
+
+### `inventory_has_items(inventory)`
+
+Returns true, if the inventory is not empty, false if it is empty, and null, if its not an inventory.
+
+inventory_has_items(player()) => true + inventory_has_items(x,y,z) => false // empty chest + inventory_has_items(block(pos)) => null // stone ++ +### `inventory_get(inventory, slot)` + +Returns the item in the corresponding inventory slot, or null if slot empty or inventory is invalid. You can use +negative numbers to indicate slots counted from 'the back'. + +
+inventory_get(player(), 0) => null // nothing in first hotbar slot
+inventory_get(x,y,z, 5) => ['stone', 1, {}]
+inventory_get(player(), -1) => ['diamond_pickaxe', 1, {Damage:4}] // slightly damaged diamond pick in the offhand
+
+
+### `inventory_set(inventory, slot, count, item?, nbt?)`
+
+Modifies or sets a stack in inventory. specify count 0 to empty the slot. If item is not specified, keeps existing
+item, just modifies the count. If item is provided - replaces current item. If nbt is provided - adds a tag to the
+stack at slot. Returns previous stack in that slot.
+
+
+inventory_set(player(), 0, 0) => ['stone', 64, {}] // player had a stack of stone in first hotbar slot
+inventory_set(player(), 0, 6) => ['diamond', 64, {}] // changed stack of diamonds in player slot to 6
+inventory_set(player(), 0, 1, 'diamond_axe','{Damage:5}') => null //added slightly damaged pick to first player slot
+
+
+### `inventory_find(inventory, item, start_slot?, ), inventory_find(inventory, null, start_slot?)`
+
+Finds the first slot with a corresponding item in the inventory, or if queried with null: the first empty slot.
+Returns slot number if found, or null otherwise. Optional start_slot argument allows to skip all preceeding slots
+allowing for efficient (so not slot-by-slot) inventory search for items.
+
++inventory_find(player(), 'stone') => 0 // player has stone in first hotbar slot +inventory_find(player(), null) => null // player's inventory has no empty spot +while( (slot = inventory_find(p, 'diamond', slot)) != null, 41, drop_item(p, slot) ) + // spits all diamonds from player inventory wherever they are +inventory_drop(x,y,z, 0) => 64 // removed and spawned in the world a full stack of items ++ +### `inventory_remove(inventory, item, amount?)` + +Removes amount (defaults to 1) of item from inventory. If the inventory doesn't have the defined amount, nothing +happens, otherwise the given amount of items is removed wherever they are in the inventory. Returns boolean +whether the removal operation was successful. Easiest way to remove a specific item from player inventory +without specifying the slot. + +
+inventory_remove(player(), 'diamond') => 1 // removed diamond from player inventory +inventory_remove(player(), 'diamond', 100) => 0 // player doesn't have 100 diamonds, nothing happened ++ +### `drop_item(inventory, slot, amount?, )` + +Drops the items from indicated inventory slot, like player that Q's an item or villager, that exchanges food. +You can Q items from block inventories as well. default amount is 0 - which is all from the slot. +NOTE: hoppers are quick enough to pick all the queued items from their inventory anyways. +Returns size of the actual dropped items. + +
+inventory_drop(player(), 0, 1) => 1 // Q's one item on the ground +inventory_drop(x,y,z, 0) => 64 // removed and spawned in the world a full stack of items +diff --git a/docs/scarpet/api/Overview.md b/docs/scarpet/api/Overview.md new file mode 100644 index 00000000..4f6b0e74 --- /dev/null +++ b/docs/scarpet/api/Overview.md @@ -0,0 +1,13 @@ +# Minecraft specific API and `scarpet` language add-ons and commands + +Here is the gist of the Minecraft related functions. Otherwise the CarpetScript could live without Minecraft. + +## Dimension warning + +One note, which is important is that most of the calls for entities and blocks would refer to the current +dimension of the caller, meaning, that if we for example list all the players using `player('all')` function, +if a player is in the other dimension, calls to entities and blocks around that player would point incorrectly. +Moreover, running commandblocks in the spawn chunks would mean that commands will always refer to the overworld +blocks and entities. In case you would want to run commands across all dimensions, just run three of them, +using `/execute in overworld/the_nether/the_end run script run ...` and query players using `player('*')`, +which only returns players in current dimension, or use `in_dimension(expr)` function. \ No newline at end of file diff --git a/docs/scarpet/api/ScriptCommand.md b/docs/scarpet/api/ScriptCommand.md new file mode 100644 index 00000000..0ac2ff36 --- /dev/null +++ b/docs/scarpet/api/ScriptCommand.md @@ -0,0 +1,185 @@ +# `/script run` command + +Primary way to input commands. The command executes in the context, position, and dimension of the executing player, +commandblock, etc... The command receives 4 variables, `x`, `y`, `z` and `p` indicating position and +the executing entity of the command. You will receive tab completion suggestions as you type your code suggesting +functions and global variables. It is advisable to use `/execute in ... at ... as ... run script run ...` or similar, +to simulate running commands in a different scope. + +# `/script load / unload
+foo = 1; +//This is a comment +bar = 2; +// This never worked, so I commented it out +// baz = foo() ++ +### `/script load/unload
+/script run example_function(const, phrase, price) -> print(const+' '+phrase+' '+price) +/script invoke example_function pi costs 5 ++ +### `/script invokepoint
+/script outline 0 100 0 -40 60 -40 40 140 40 "x*x+y*y+z*z < 32*32" white_stained_glass replace air +/script outline 0 100 0 -40 60 -40 40 140 40 "x*x+y*y+z*z <= 32*32" white_stained_glass replace air +/script outline 0 100 0 -40 60 -40 40 140 40 "x*x+y*y+z*z < 32.5*32.5" white_stained_glass replace air +/script fill 0 100 0 -40 60 -40 40 140 40 "floor(sqrt(x*x+y*y+z*z)) == 32" white_stained_glass replace air +/script fill 0 100 0 -40 60 -40 40 140 40 "round(sqrt(x*x+y*y+z*z)) == 32" white_stained_glass replace air +/script fill 0 100 0 -40 60 -40 40 140 40 "ceil(sqrt(x*x+y*y+z*z)) == 32" white_stained_glass replace air +/draw sphere 0 100 0 32 white_stained_glass replace air // fluffy ball round(sqrt(x*x+y*y+z*z)-rand(abs(y)))==32 ++ +The last method is the one that world edit is using (part of carpet mod). It turns out that the outline method +with `32.5` radius, fill method with `round` function and draw command are equivalent + +# `script stop/script resume` command + +`/script stop` allows to stop execution of any script currently running that calls the `game_tick()` function which +allows the game loop to regain control of the game and process other commands. This will also make sure that all +current and future programs will stop their execution. Execution of all programs will be prevented +until `/script resume` command is called. + +Lets look at the following example. This is a program computes Fibonacci number in a recursive manner: + +
+fib(n) -> if(n<3, 1, fib(n-1)+fib(n-2) ); fib(8) ++ +That's really bad way of doing it, because the higher number we need to compute the compute requirements will +rise exponentially with `n`. It takes a little over 50 milliseconds to do fib(24), so above one tick, but about +a minute to do fib(40). Calling fib(40) will not only freeze the game, but also you woudn't be able to interrupt +its execution. We can modify the script as follows + +
+fib(n) -> ( game_tick(50); if(n<3, 1, fib(n-1)+fib(n-2) ) ); fib(40) ++ +But this would never finish as such call would finish after `~ 2^40` ticks. To make our computations responsive, +yet able to respond to user interactions, other commands, as well as interrupt execution, we could do the following: + +
+fib(n) -> ( if(n==23, game_tick(50) ); if(n<3, 1, fib(n-1)+fib(n-2) ) ); fib(40) ++ +This would slow down the computation of fib(40) from a minute to two, but allows the game to keep continue running +and be responsive to commands, using about half of each tick to advance the computation. Obviously depending on the +problem, and available hardware, certain things can take more or less time to execute, so portioning of work with +calling `gametick` should be balanced in each case separately diff --git a/docs/scarpet/language/Containers.md b/docs/scarpet/language/Containers.md new file mode 100644 index 00000000..3064b89f --- /dev/null +++ b/docs/scarpet/language/Containers.md @@ -0,0 +1,241 @@ +# Lists, Maps and API support for Containers + +Scarpet supports basic container types: lists and maps (aka hashmaps, dicts etc..) + +## Container manipulation + +Here is a list of operations that work on all types of containers: lists, maps, as well as other Minecraft specific +modifyable containers, like NBTs + +### `get(container, address, ...), get(lvalue), ':' operator` + +Returns the value at `address` element from the `value`. For lists it indicates an index, use negative numbers to +reach elements from the end of the list. `get` call will always be able to find the index. In case there is few +items, it will loop over + +for maps, retrieves the value under the key specified in the `address` or null otherwise + +[Minecraft specific usecase]: In case `value` is of `nbt` type, uses address as the nbt path to query, returning null, +if path is not found, one value if there was one match, or list of values if result is a list. Returned elements can +be of numerical type, string texts, or another compound nbt tags + +In case to simplify the access with nested objects, you can add chain of addresses to the arguments of `get` rather +than calling it multiple times. `get(get(foo,a),b)` is equivalent to `get(foo, a, b)`, or `foo:a:b`. + +
+get(l(range(10)), 5) => 5
+get(l(range(10)), -1) => 9
+get(l(range(10)), 10) => 0
+l(range(10)):93 => 3
+get(player() ~ 'nbt', 'Health') => 20 // inefficient way to get player health, use player() ~ 'health' instead
+get(m( l('foo',2), l('bar',3), l('baz',4) ), 'bar') => 3
+
+
+### `has(container, address, ...), has(lvalue)`
+
+Similar to `get`, but returns boolean value indicating if the given index / key / path is in the container.
+Can be used to determine if `get(...)==null` means the element doesn't exist, or the stored value for this
+address is `null`, and is cheaper to run than `get`.
+
+Like get, it can accept multiple addresses for chains in nested containers. In this case `has(foo:a:b)` is
+equivalent to `has(get(foo,a), b)` or `has(foo, a, b)`
+
+### `delete(container, address, ...), delete(lvalue)`
+
+Removes specific entry from the container. For the lists - removes the element and shrinks it. For maps, it
+removes the key from the map, and for nbt - removes content from a given path. For lists and maps returns previous
+entry at the address, for nbt's - number of removed objects, with 0 indicating that the original value was unaffected.
+
+Like with the `get` and `has`, `delete` can accept chained addresses, as well as l-value container access, removing
+the value from the leaf of the path provided, so `delete(foo, a, b)` is the
+same as `delete(get(foo,a),b)` or `delete(foo:a:b)`
+
+Returns true, if container was changed, false, if it was left unchanged, and null if operation was invalid.
+
+### `put(container, address, value), put(container, address, value, mode), put(lvalue, value)`
+
+**Lists**
+
+Modifies the container by replacing the value under the address with the supplied `value`. For lists, a valid
+index is required, but can be negative as well to indicate positions from the end of the list. If `null` is
+supplied as the address, it always means - add to the end of the list.
+
+There are three modes that lists can have items added to them:
+
+* `replace`(default): Replaces item under given index(address). Doesn't change the size of the array
+unless `null` address is used, which is an exception and then it appends to the end
+* `insert`: Inserts given element at a specified index, shifting the rest of the array to make space for the item.
+Note that index of -1 points to the last element of the list, thus inserting at that position and moving the previous
+last element to the new last element position. To insert at the end, use `+=` operator, or `null` address in put
+* `extend`: treats the supplied value as an iterable set of values to insert at a given index, extending the list
+by this amount of items. Again use `null` address/index to point to the end of the list
+
+Due to the extra mode parameter, there is no chaining for `put`, but you can still use l-value container access to
+indicate container and address, so `put(foo, key, value)` is the same as `put(foo:key, value)` or `foo:key=value`
+
+Returns true, if container got modified, false otherwise, and null if operation was invalid.
+
+**Maps**
+
+For maps there are no modes available (yet, seems there is no reason to). It replaces the value under the supplied
+key (address), or sets it if not currently present.
+
+**NBT Tags**
+
+The address for nbt values is a valid nbt path that you would use with `/data` command, and tag is any tag that
+would be applicable for a given insert operation. Note that to distinguish between proper types (like integer types,
+you need to use command notation, i.e. regular ints is `123`, while byte size int would be `123b` and an explicit
+string would be `"5"`, so it helps that scarpet uses single quotes in his strings. Unlike for lists and maps, it
+returns the number of affected nodes, or 0 if none were affected.
+
+There are three modes that NBT tags can have items added to them:
+
+* `replace`(default): Replaces item under given path(address). Removes them first if possible, and then adds given
+element to the supplied position. The target path can indicate compound tag keys, lists, or individual elements
+of the lists.
+* `
+a = l(1, 2, 3); put(a, 1, 4); a => [1, 4, 3]
+a = l(1, 2, 3); put(a, null, 4); a => [1, 2, 3, 4]
+a = l(1, 2, 3); put(a, 1, 4, 'insert'); a => [1, 4, 2, 3]
+a = l(1, 2, 3); put(a, null, l(4, 5, 6), 'extend'); a => [1, 2, 3, 4, 5, 6]
+a = l(1, 2, 3); put(a, 1, l(4, 5, 6), 'extend'); a => [1, 4, 5, 6, 2, 3]
+a = l(l(0,0,0),l(0,0,0),l(0,0,0)); put(a.1, 1, 1); a => [[0, 0, 0], [0, 1, 0], [0, 0, 0]]
+a = m(1,2,3,4); put(a, 5, null); a => {1: null, 2: null, 3: null, 4: null, 5: null}
+tag = nbt('{}'); put(tag, 'BlockData.Properties', '[1,2,3,4]'); tag => {BlockData:{Properties:[1,2,3,4]}}
+tag = nbt('{a:[{lvl:3},{lvl:5},{lvl:2}]}'); put(tag, 'a[].lvl', 1); tag => {a:[{lvl:1},{lvl:1},{lvl:1}]}
+tag = nbt('{a:[{lvl:[1,2,3]},{lvl:[3,2,1]},{lvl:[4,5,6]}]}'); put(tag, 'a[].lvl', 1, 2); tag
+ => {a:[{lvl:[1,2,1,3]},{lvl:[3,2,1,1]},{lvl:[4,5,1,6]}]}
+tag = nbt('{a:[{lvl:[1,2,3]},{lvl:[3,2,1]},{lvl:[4,5,6]}]}'); put(tag, 'a[].lvl[1]', 1); tag
+ => {a:[{lvl:[1,1,3]},{lvl:[3,1,1]},{lvl:[4,1,6]}]}
+
+
+## List operations
+
+### `l(values ...), l(iterator)`
+
+Creates a list of values of the expressions passed as parameters. It can be used as an L-value and if all
+elements are variables, you coujld use it to return multiple results from one function call, if that
+function returns a list of results with the same size as the `l` call uses. In case there is only one
+argument and it is an iterator (vanilla expression specification has `range`, but Minecraft API implements
+a bunch of them, like `diamond`), it will convert it to a proper list. Iterators can only be used in high order
+functions, and are treated as empty lists, unless unrolled with `l`
+
++l(1,2,'foo') => [1, 2, foo] +l() => [] (empty list) +l(range(10)) => [0, 1, 2, 3, 4, 5, 6, 7, 8, 9] +l(1, 2) = l(3, 4) => Error: l is not a variable +l(foo, bar) = l(3,4); foo==3 && bar==4 => 1 +l(foo, bar, baz) = l(2, 4, 6); l(min(foo, bar), baz) = l(3, 5); l(foo, bar, baz) => [3, 4, 5] ++ +In the last example `l(min(foo, bar), baz)` creates a valid L-value, as min(foo, bar) finds the lower of the +variables (in this case `foo`) creating a valid assignable L-list of [foo, baz], and these values +will be assigned new values + +### `join(delim, list), join(delim, values ...)` + +Returns a string that contains joined elements of the list, iterator, or all values, +concatenated with `delim` delimiter + +
+join('-',range(10)) => 0-1-2-3-4-5-6-7-8-9
+join('-','foo') => foo
+join('-', 'foo', 'bar') => foo-bar
+
+
+### `split(delim, expr)`
+
+Splits a string undr `expr` by `delim` which can be a regular expression
+
+
+split('',foo) => [f, o, o]
+split('.','foo.bar') => []
+split('\\.','foo.bar') => [foo, bar]
+
+
+### `slice(expr, from, to?)`
+
+extracts a substring, or sublist (based on the type of the result of the expression under expr with
+starting index of `from`, and ending at `to` if provided, or the end, if omitted
+
+
+slice(l(0,1,2,3,4,5), 1, 3) => [1, 2, 3]
+slice('foobar', 0, 1) => 'f'
+slice('foobar', 3) => 'bar'
+slice(range(10), 3, 5) => [3, 4, 5]
+slice(range(10), 5) => [5, 6, 7, 8, 9]
+
+
+### `sort(list), sort(values ...)`
+
+Sorts in the default sortographical order either all arguments, or a list if its the only argument.
+It returns a new sorted list, not affecting the list passed to the argument
+
+sort(3,2,1) => [1, 2, 3]
+sort('a',3,11,1) => [1, 3, 11, 'a']
+list = l(4,3,2,1); sort(list) => [1, 2, 3, 4]
+
+
+### `sort_key(list, key_expr)`
+
+Sorts a copy of the list in the order or keys as defined by the `key_expr` for each element
+
++sort_key([1,3,2],_) => [1, 2, 3] +sort_key([1,3,2],-_) => [3, 2, 1] +sort_key(l(range(10)),rand(1)) => [1, 0, 9, 6, 8, 2, 4, 5, 7, 3] +sort_key(l(range(20)),str(_)) => [0, 1, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 2, 3, 4, 5, 6, 7, 8, 9] ++ +### `range(to), range(from, to), range(from, to, step)` + +Creates a range of numbers from `from`, no greater/larger than `to`. The `step` parameter dictates not only the +increment size, but also direction (can be negative). The returned value is not a proper list, just the iterator +but if for whatever reason you need a proper list with all items evaluated, use `l(range(to))`. +Primarily to be used in higher order functions + +
+range(10) => [...] +l(range(10)) => [0, 1, 2, 3, 4, 5, 6, 7, 8, 9] +map(range(10),_*_) => [0, 1, 4, 9, 16, 25, 36, 49, 64, 81] +reduce(range(10),_a+_, 0) => 45 +range(5,10) => [5, 6, 7, 8, 9] +range(20, 10, -2) => [20, 18, 16, 14, 12] ++ +### `element(list, index)(deprecated)` + +Legacy support for older method that worked only on lists. Please use `get(...)` for equivalent support, or `.` +operator. Also previous unique behaviours with `put` on lists has been removed to support all type of +container types. + +## Map operations + +Scarpet supports map structures, aka hashmaps, dicts etc. Map structure can also be used, with `null` values as sets. +Apart from container access functions, (`. , get, put, has, delete`), the following functions: + +### `m(values ...), m(iterator), m(key_value_pairs)` + +creates and initializes a map with supplied keys, and values. If the arguments contains a flat list, these are all +treated as keys with no value, same goes with the iterator - creates a map that behaves like a set. If the +arguments is a list of lists, they have to have two elements each, and then first is a key, and second, a value + +
+m(1,2,'foo') => {1: null, 2: null, foo: null}
+m() => {} (empty map)
+m(range(10)) => {0: null, 1: null, 2: null, 3: null, 4: null, 5: null, 6: null, 7: null, 8: null, 9: null}
+m(l(1, 2), l(3, 4)) => {1: 2, 3: 4}
+reduce(range(10), put(_a, _, _*_); _a, m())
+ => {0: 0, 1: 1, 2: 4, 3: 9, 4: 16, 5: 25, 6: 36, 7: 49, 8: 64, 9: 81}
+
+
+### `keys(map), values(map), pairs(map)`
+
+Returns full lists of keys, values and key-value pairs (2-element lists) for all the entries in the map
diff --git a/docs/scarpet/language/FunctionsAndControlFlow.md b/docs/scarpet/language/FunctionsAndControlFlow.md
new file mode 100644
index 00000000..03accaec
--- /dev/null
+++ b/docs/scarpet/language/FunctionsAndControlFlow.md
@@ -0,0 +1,170 @@
+# User-defined functions and program control flow
+
+## Writing programs with more than 1 line
+
+### `Operator ;`
+
+To effectively write programs that have more than one line, a programmer needs way to specify a sequence of commands
+that execute one after another. In `scarpet` this can be achieved with `;`. Its an operator, and by separating
+statements with semicolons. And since whitespaces and
+`$` (commandline visible newline separator)
+sign are all treats as whitespaces, how you layout your code doesn't matter, as long as it is readable to everyone involved.
+
++expr; +expr; +expr; +expr ++ +Notice that the last expression is not followed by a semicolon. Since instruction separation is functional +in `scarpet`, and not barely an instruction delimiter, terminating the code with a dangling operator wouldn't +be valid. Having said that, since many programming languages don't care about the number of op terminators +programmers use, carpet preprocessor will remove all unnecessary semicolons from scripts when compiled. + +In general `expr; expr; expr; expr` is equivalent to `(((expr ; expr) ; expr) ; expr)`. + +Result of the evaluated expression is the same as the result of the second expression, but first expression +is also evaluated for side-effects + +
+expr1 ; expr2 => expr2 // with expr1 as a side-effect ++ +## Global variables + +All defined functions are compiled, stored persistently, and available globally - accessible to all other scripts. +Functions can only be undefined via call to `undef('fun')`, which would erase global entry for function `fun`. +Since all variables have local scope inside each function, one way to share large objects is via global variables + +Any variable that is used with a name that starts with `'global_'` will be stored and accessible globally, not, +inside current scope. It will also persist across scripts, so if a procedure needs to use its own construct, it +needs to define it, or initialize it explicitly, or undefine it via `undef` + +
+a() -> global_list+=1; global_list = l(1,2,3); a(); a(); global_list // => [1,2,3,1,1] ++ +### `Operator ->` + +To organize code better than a flat sequence of operations, one can define functions. Definition is correct +if has the following form + +
+fun(args, ...) -> expr ++ +Where `fun(args, ...)` is a function signature indicating function name, number of arguments, and their names, +and expr is an expression (can be complex) that is evaluated when `fun` is called. Names in the signature don't +need to be used anywhere else, other occurrences of these names will be masked in this function scope. Function +call creates new scope for variables inside `expr`, so all non-global variables are not visible from the caller +scope. All parameters are passed by value to the new scope, including lists and other containers, however their +copy will be shallow. + +The function returns its name as a string, which means it can be used to call it later with the `call` function + +Using `_` as the function name creates anonymous function, so each time `_` function is defined, it will be given +a unique name, which you can pass somewhere else to get this function `call`ed. + +
+a(lst) -> lst+=1; list = l(1,2,3); a(list); a(list); list // => [1,2,3] ++ +In case the inner function wants to operate and modify larger objects, lists from the outer scope, but not global, +it needs to use `outer` function in function signature + +### `outer(arg)` + +`outer` function can only be used in the function signature, and it will cause an error everywhere else. It +saves the value of that variable from the outer scope and allows its use in the inner scope. This is a similar +behaviour to using outer variables in lambda function definitions from Java, except here you have to specify +which variables you want to use, and borrow + +This mechanism can be used to use static mutable objects without the need of using `global_...` variables + +
+list = l(1,2,3); a(outer(list)) -> list+=1; a(); a(); list // => [1,2,3,1,1] ++ +The return value of a function is the value of the last expression. This as the same effect as using outer or +global lists, but is more expensive + +
+a(lst) -> lst+=1; list = l(1,2,3); list=a(list); list=a(list); list // => [1,2,3,1,1] ++ +Ability to combine more statements into one expression, with functions, passing parameters, and global and outer +scoping allow to organize even larger scripts + +### `import(module_name, symbols ...)` + +Imports symbols from other apps and libraries into the current one: global variables or functions, allowing to use +them in the current app. This include other symbols imported by these modules. Scarpet supports cicular dependencies, +but if symbols are used directly in the module body rather than functions, it may not be able to retrieve them. +Returns full list of available symbols that could be imported from this module, which can be used to debug import +issues, and list contents of libraries. + +### `call(function, args.....)` + +calls a user defined function with specified arguments. It is equivalent to calling `function(args...)` directly +except you can use it with function value, or name instead. This means you can pass functions to other user defined +functions as arguments and call them with `call` internally. And since function definitions return the defined +function, they can be defined in place as anonymous functions. + +Little technical note: the use of `_` in expression passed to built in functions is much more efficient due to not +creating new call stacks for each invoked function, but anonymous functions is the only mechanism available for +programmers with their own lambda arguments + +
+my_map(list, function) -> map(list, call(function, _)); +my_map(l(1,2,3), _(x) -> x*x); // => [1,4,9] +profile_expr(my_map(l(1,2,3), _(x) -> x*x)); // => ~32000 +sq(x) -> x*x; profile_expr(my_map(l(1,2,3), 'sq')); // => ~36000 +sq = (_(x) -> x*x); profile_expr(my_map(l(1,2,3), sq)); // => ~36000 +profile_expr(map(l(1,2,3), _*_)); // => ~80000 ++ +## Control flow + +### `return(expr?)` + +Sometimes its convenient to break the organized control flow, or it is not practical to pass the final result value of +a function to the last statement, in this case a return statement can be used + +If no argument is provided - returns null value. + +
+def() -> ( + expr1; + expr2; + return(expr3); // function terminates returning expr3 + expr4; // skipped + expr5 // skipped +) ++ +In general its cheaper to leave the last expression as a return value, rather than calling +returns everywhere, but it would often lead to a messy code. + +### `exit(expr?)` + +It terminates entire program passing `expr` as the result of the program execution, or null if omitted. + +### `try(expr, catch_expr(_)?) ... throw(value?)` + +`try` function evaluates expression, and continues further unless `throw` function is called anywhere +inside `expr`. In that case the `catch_expr` is evaluates with `_` set to the argument `throw` was called with. +This mechanic accepts skipping thrown value - it throws null instead, and catch expression - then try returns +null as well This mechanism allows to terminate large portion of a convoluted call stack and continue program +execution. There is only one level of exceptions currently in carpet, so if the inner function also defines +the `try` catchment area, it will received the exception first, but it can technically rethrow the value its +getting for the outer scope. Unhandled throw acts like an exit statement. + +### `if(cond, expr, cond?, expr?, ..., default?)` + +If statement is a function that takes a number of conditions that are evaluated one after another and if any of +them turns out true, its `expr` gets returned, otherwise, if all conditions fail, the return value is `default` +expression, or `null` if default is skipped + +`if` function is equivalent to `if (cond) expr; else if (cond) expr; else default;` from Java, +just in a functional form diff --git a/docs/scarpet/language/LoopsAndHigherOrderFunctions.md b/docs/scarpet/language/LoopsAndHigherOrderFunctions.md new file mode 100644 index 00000000..d79eb59f --- /dev/null +++ b/docs/scarpet/language/LoopsAndHigherOrderFunctions.md @@ -0,0 +1,132 @@ +# Loops, and higher order functions + +Efficient use of these functions can greatly simplify your programs and speed them up, as these functions will +internalize most of the operations that need to be applied on multiple values at the same time. Most of them take +a `list` argument which can be any iterable structure in scarpet, including generators, like `rect`, or `range`, +and maps, where the iterator returns all the map keys + +## Loops + +### `break(), break(expr), continue(), continue(expr)` + +These allow to control execution of a loop either skipping current iteration code, using `continue`, or finishing the +current loop, using `break`. `break` and `continue` can only be used inside `for, while, loop, map, filter and reduce` +functions, while `break` can be used in `first` as well. Outside of the internal expressions of these functions, +calling `break` or `continue` will cause an error. In case of the nexted loops, and more complex setups, use +custom `try` and `throw` setup. + +Please check corresponding loop function description what `continue` and `break` do in their contexts, but in +general case, passed values to `break` and `continue` will be used in place of the return value of the internal +iteration expression. + +### `for(list,expr(_,_i))` + +Evaluates expression over list of items from the `list`. Supplies `_`(value) and `_i`(iteration number) to the `expr`. + +Returns the number of times `expr` was successful. Uses `continue` and `break` argument in place of the returned +value from the `expr`(if supplied), to determine if the iteration was successful. + +
+check_prime(n) -> !first( range(2, sqrt(n)+1), !(n % _) ); +for(range(1000000,1100000),check_prime(_)) => 7216 ++ +From which we can learn that there is 7216 primes between 1M and 1.1M + +### `while(cond, limit)` + +Evaluates expression `expr` repeatedly until condition `cond` becomes false, but not more than `limit` times. +Returns the result of the last `expr` evaluation, or `null` if nothing was successful. Both `expr` and `cond` will +recveived a bound variable `_` indicating current iteration, so its a number. + +
+while(a<100,10,a=_*_) => 81 // loop exhausted via limit +while(a<100,20,a=_*_) => 100 // loop stopped at condition, but a has already been assigned +while(_*_<100,20,a=_*_) => 81 // loop stopped at condition, before a was assigned a value ++ +### `loop(num,expr(_),exit(_)?)` + +Evaluates expression `expr`, `num` number of times. code>expr receives `_` system variable indicating the iteration. + +
+loop(5, game_tick()) => repeat tick 5 times +list = l(); loop(5, x = _; loop(5, list += l(x, _) ) ); list + // double loop, produces: [[0, 0], [0, 1], [0, 2], [0, 3], [0, 4], [1, 0], [1, 1], ... , [4, 2], [4, 3], [4, 4]] ++ +In this small example we will search for first 10 primes, apparently including 0: + +
+check_prime(n) -> !first( range(2, sqrt(n)+1), !(n % _) ); +primes = l(); +loop(10000, if(check_prime(_), primes += _ ; if (length(primes) >= 10, break()))); +primes +// outputs: [0, 1, 2, 3, 5, 7, 11, 13, 17, 19] ++ +## Higher Order Functions + +### `map(list,expr(_,_i))` + +Converts a `list` of values, to another list where each value is result of an expression `v = expr(_, _i)` +where `_` is passed as each element of the list, and `_i` is the index of such element. If `break` is called the +map returns whatever collected thus far. If `continue` and `break` are used with supplied argument, it is used in +place of the resulting map element, otherwise current element is skipped. + +
+map(range(10), _*_) => [0, 1, 4, 9, 16, 25, 36, 49, 64, 81]
+map(players('*'), _+' is stoopid') [gnembon is stoopid, herobrine is stoopid]
+
+
+### `filter(list,expr(_,_i))`
+
+filters `list` elements returning only these that return positive result of the `expr`. With `break` and `continue`
+statements, the supplied value can be used as a boolean check instead.
+
+
+filter(range(100), !(_%5), _*_>1000) => [0, 5, 10, 15, 20, 25, 30]
+map(filter(entity_list('*'),_=='Witch'), query(_,'pos') ) => [[1082.5, 57, 1243.5]]
+
+
+### `first(list,expr(_,_i))`
+
+Finds and returns the first item in the list that satisfies `expr`. It sets `_` for current element value,
+and `_i` for index of that element. `break` can be called inside the iteration code, using its argument value
+instead of the current item. `continue` has no sense and cannot be called inside `first` call.
+
++first(range(1000,10000), n=_; !first( range(2, sqrt(n)+1), !(n % _) ) ) => 1009 // first prime after 1000 ++ +Notice in the example above, that we needed to rename the outer `_` to be albe to use in in the inner `first` call + +### `all(list,expr(_,_i))` + +Returns `true` if all elements on the list satisfy the condition. Its roughly equivalent +to `all(list,expr) <=> for(list,expr)==length(list)`. `expr` also receives bound `_` and `_i` variables. `break` +and `continue` have no sense and cannot be used inside of `expr` body. + +
+all([1,2,3], check_prime(_)) => 1 +all(neighbours(x,y,z), _=='stone') => 1 // if all neighbours of [x, y, z] are stone +map(filter(rect(0,4,0,1000,0,1000), l(x,y,z)=pos(_); all(rect(x,y,z,1,0,1),_=='bedrock') ), pos(_) ) + => [[-298, 4, -703], [-287, 4, -156], [-269, 4, 104], [242, 4, 250], [-159, 4, 335], [-208, 4, 416], [-510, 4, 546], [376, 4, 806]] + // find all 3x3 bedrock structures in the top bedrock layer +map( filter( rect(0,4,0,1000,1,1000,1000,0,1000), l(x,y,z)=pos(_); + all(rect(x,y,z,1,0,1),_=='bedrock') && for(rect(x,y-1,z,1,1,1,1,0,1),_=='bedrock')<8), + pos(_) ) => [[343, 3, -642], [153, 3, -285], [674, 3, 167], [-710, 3, 398]] + // ditto, but requiring at most 7 bedrock block in the 18 blocks below them ++ +### `reduce(list,expr(_a,_,_i), initial)` + +Applies `expr` for each element of the list and saves the result in `_a` accumulator. Consecutive calls to `expr` +can access that value to apply more values. You also need to specify the initial value to apply for the +accumulator. `break` can be used to terminate reduction prematurely. If a value is provided to `break` or `continue`, +it will be used from now on as a new value for the accumulator. + +
+reduce([1,2,3,4],_a+_,0) => 10 +reduce([1,2,3,4],_a*_,1) => 24 +\ No newline at end of file diff --git a/docs/scarpet/language/Math.md b/docs/scarpet/language/Math.md new file mode 100644 index 00000000..5331d238 --- /dev/null +++ b/docs/scarpet/language/Math.md @@ -0,0 +1,120 @@ +# Arithmetic operations + +## Basic Arithmetic Functions + +There is bunch of them - they require a number and spit out a number, doing what you would expect them to do. + +### `fact(n)` + +Factorial of a number, a.k.a `n!`, just not in `scarpet`. Gets big... quick... + +### `sqrt(n)` + +Square root. For other fancy roots, use `^`, math and yo noggin. Imagine square roots on a tree... + +### `abs(n)` + +Absolut value. + +### `round(n)` + +Closest integer value. Did you know the earth is also round? + +### `floor(n)` + +Highest integer that is still no larger then `n`. Insert a floor pun here. + +### `ceil(n)` + +First lucky integer that is not smalller than `n`. As you would expect, ceiling is typically right above the floor. + +### `ln(n)` + +Natural logarithm of `n`. Naturally. + +### `ln1p(n)` + +Natural logarithm of `n+1`. Very optimistic. + +### `log10(n)` + +Decimal logarithm of `n`. Its ceiling is the length of its floor. + +### `log(n)` + +Binary logarithm of `n`. Finally, a proper one, not like the previous 11. + +### `log1p(n)` + +Binary logarithm of `n+1`. Also always positive. + +### `mandelbrot(a, b, limit)` + +Computes the value of the mandelbrot set, for set `a` and `b` spot. Spot the beetle. Why not. + +### `min(arg, ...), min(list), max(arg, ...), max(list)` + +Compute minimum or maximum of supplied arguments assuming default sorthoraphical order. +In case you are missing `argmax`, just use `a ~ max(a)`, little less efficient, but still fun. + +Interesting bit - `min` and `max` don't remove variable associations from arguments, which means can be used as +LHS of assignments (obvious case), or argument spec in function definitions (far less obvious). + +
+a = 1; b = 2; min(a,b) = 3; l(a,b) => [3, 2] +a = 1; b = 2; fun(x, min(a,b)) -> l(a,b); fun(3,5) => [5, 0] ++ +Absolutely no idea, how the latter might be useful in practice. But since it compiles, can ship it. + +### `relu(n)` + +Linear rectifier of `n`. 0 below 0, n above. Why not. `max(0,n)` with less moral repercussions. + +## Trigonometric / Geometric Functions + +### `sin(x)` + +### `cos(x)` + +### `tan(x)` + +### `asin(x)` + +### `acos(x)` + +### `atan(x)` + +### `atan2(x,y)` + +### `sinh(x)` + +### `cosh(x)` + +### `tanh(x)` + +### `sec(x)` + +### `csc(x)` + +### `sech(x)` + +### `csch(x)` + +### `cot(x)` + +### `acot(x)` + +### `coth(x)` + +### `asinh(x)` + +### `acosh(x)` + +### `atanh(x)` + +### `rad(deg)` + +### `deg(rad)` + +Use as you wish diff --git a/docs/scarpet/language/Operators.md b/docs/scarpet/language/Operators.md new file mode 100644 index 00000000..9fc49180 --- /dev/null +++ b/docs/scarpet/language/Operators.md @@ -0,0 +1,215 @@ +# Operators + +There is a number of operators you can use inside the expressions. Those could be considered generic type operators +that apply to most data types. They also follow standard operator precedence, i.e. `2+2*2` is understood +as `2+(2*2)`, not `(2+2)*2`, otherwise they are applied from left to right, i.e. `2+4-3` is interpreted +as `(2+4)-3`, which in case of numbers doesn't matter, but since `scarpet` allows for mixing all value types +the associativity would matter, and may lead to unintended effects: + +Important operator is function definition `->` operator. It will be covered +in {@link carpet.script.Expression#UserDefinedFunctionsAndControlFlow} + +
+'123'+4-2 => ('123'+4)-2 => '1234'-2 => '134'
+'123'+(4-2) => '123'+2 => '1232'
+3*'foo' => 'foofoofoo'
+1357-5 => 1352
+1357-'5' => 137
+3*'foo'-'o' => 'fff'
+l(1,3,5)+7 => l(8,10,12)
+
+
+As you can see, values can behave differently when mixed with other types in the same expression.
+In case values are of the same types, the result tends to be obvious, but `Scarpet` tries to make sense of whatever
+it has to deal with
+
+## Operator Precedence
+
+Here is the complete list of operators in `scarpet` including control flow operators. Note, that commas and brackets
+are not technically operators, but part of the language, even if they look like them:
+
+* Match, Get `~ :`
+* Unary `+ - !`
+* Exponent `^`
+* Multiplication `* / %`
+* Addition `+ -`
+* Comparison `== != > >= <= <`
+* Logical And`&&`
+* Logical Or `||`
+* Assignment `= += <>`
+* Definition `->`
+* Next statement`;`
+* Comma `,`
+* Bracket `( )`
+
+### `Get, Accessor Operator :`
+
+Operator version of the `get(...)` function to access elements of lists, maps, and potentially other containers
+(i.e. NBTs). It is important to distinguish from `~` operator, which is a matching operator, which is expected to
+perform some extra computations to retrieve the result, while `:` should be straightforward and immediate, and
+the source object should behave like a container and support full container API,
+meaning `get(...)`, `put(...)`, `delete(...)`, and `has(...)` functions
+
+For certain operators and functions (get, put, delete, has, =, +=) objects can use `:` annotated fields as l-values,
+meaning construct like `foo:0 = 5`, would act like `put(foo, 0, 5)`, rather than `get(foo, 0) = 5`,
+which would result in an error.
+
+TODO: add more information about l-value behaviour.
+
+### `Matching Operator ~`
+
+This operator should be understood as 'matches', 'contains', 'is_in', or 'find me some stuff about something else.
+For strings it matches the right operand as a regular expression to the left, returning the first match.
+This can be used to extract information from unparsed nbt's in a more convoluted way (use `get(...)` for
+more appropriate way of doing it). For lists it checks if an element is in the list, and returns the
+index of that element, or `null` if no such element was found, especially that the use of `first(...)`
+function will not return the index. Currently it doesn't have any special behaviour for numbers - it checks for
+existence of characters in string representation of the left operand with respect of the regular expression on
+the right hand side.
+
+In Minecraft API portion `entity ~ feature` is a shortcode for `query(entity,feature)` for queries that do not take
+any extra arguments.
+
+
+l(1,2,3) ~ 2 => 1
+l(1,2,3) ~ 4 => null
+'foobar' ~ '.b' => 'ob'
+player('*') ~ 'gnembon' // null unless player gnembon is logged in (better to use player('gnembon') instead
+p ~ 'sneaking' // if p is an entity returns whether p is sneaking
+
+
+Or a longer example of an ineffective way to searching for a squid
+
+
+entities = entities_area('all',x,y,z,100,10,100);
+sid = entities ~ 'Squid';
+if(sid != null, run('execute as '+query(get(entities,sid),'id')+' run say I am here '+query(get(entities,sid),'pos') ) )
+
+
+Or an example to find if a player has specific enchantment on a held axe (either hand) and get its level
+(not using proper NBTs query support via `get(...)`):
+
+
+global_get_enchantment(p, ench) -> (
+$ for(l('main','offhand'),
+$ holds = query(p, 'holds', _);
+$ if( holds,
+$ l(what, count, nbt) = holds;
+$ if( what ~ '_axe' && nbt ~ ench,
+$ lvl = max(lvl, number(nbt ~ '(?<=lvl:)\\d') )
+$ )
+$ )
+$ );
+$ lvl
+$);
+/script run global_get_enchantment(players(), 'sharpness')
+
+
+### `Basic Arithmetic Operators + - * /`
+
+Allows to add the results of two expressions. If the operands resolve to numbers, the result is arithmetic operation.
+In case of strings, adding or subtracting from a string results in string concatenation and removal of substrings
+from that string. Multiplication of strings and numbers results in repeating the string N times and division results
+in taking the first k'th part of the string, so that `str*n/n ~ str` In case first operand is a list, either it
+results in a new list with all elements modified one by one with the other operand, or if the operand is a list
+with the same number of items - element-wise addition/subtraction
+
+Examples:
+
++2+3 => 5 +'foo'+3+2 => 'foo32' +'foo'+(3+2) => 'foo5' +3+2+'bar' => '5bar' +'foo'*3 => 'foofoofoo' +'foofoofoo' / 3 => 'foo' +'foofoofoo'-'o' => 'fff' +l(1,2,3)+1 => l(2,3,4) +b = l(100,63,100); b+l(10,0,10) => l(110,63,110) ++ +### `Just Operators % ^` + +The modulo and exponent (power) operators work only if both operands are numbers + +
pi^pi%euler => 1.124.... +-9 % 4 => -1 +9 % -4 => 0 ¯\_(ツ)_/¯ Java +-3 ^ 2 => 9 +-3 ^ pi => // Error ++ +### `Comparison Operators == != < > <= >=` + +Allows to compare the results of two expressions. For numbers it is considers arithmetic order of numbers, for +strings - lexicographical, nulls are always 'less' than everything else, and lists check their elements - +if the sizes are different, the size matters, otherwise, pairwise comparisons for each elements are performed. +The same order rules than with all these operators are used with the default sortographical order as used by `sort` +function. All of these are true: + +
+null == null +null != false +0 == false +1 == true +null < 0 +null < -1000 +1000 < 'a' +'bar' < 'foo' +3 == 3.0 ++ +### `Logical Operators && ||` + +These operator compute respective boolean operation on the operands. What it important is that if calculating of the +second operand is not necessary, it won't be evaluated, which means one can use them as conditional statements. In +case of success returns first positive operand (`||`) or last one (`&&`). + +
+true || false => 1
+null || false => 0
+null != false || run('kill gnembon') => 1 // gnembon survives
+null != false && run('kill gnembon') => 0 // when cheats not allowed
+null != false && run('kill gnembon') => 1 // gnembon dies, cheats allowed
+
+
+### `Assignment Operators = <> +=`
+
+A set of assignment operators. All require bounded variable on the LHS, `<>` requires bounded arguments on the
+right hand side as well (bounded, meaning being variables). Additionally they can also handle list constructors
+with all bounded variables, and work then as list assignment operators. When `+=` is used on a list, it extends
+that list of that element, and returns the list (old == new). `scarpet` doesn't support currently removal of items.
+Removal of items can be obtaine via `filter` command, and reassigning it fo the same variable. Both operations would
+require rewriting of the array anyways.
+
++a = 5 => a == 5 +l(a,b,c) = l(3,4,5) => a==3, b==4, c==5 +l(minx,maxx) = sort(xi,xj); // minx assumes min(xi, xj) and maxx, max(xi, xj) +l(a,b,c,d,e,f) = l(range(6)); l(a,b,c) <> l(d,e,f); l(a,b,c,d,e,f) => [3,4,5,0,1,2] +a = l(1,2,3); a += 4 => [1,2,3,4] +a = l(1,2,3,4); a = filter(a,_!=2) => [1,3,4] ++ +### `Unary Operators - +` + +Require a number, flips the sign. One way to assert it's a number is by crashing the script. gg. + +
+-4 => -4 ++4 => 4 ++'4' // Error message ++ +### `Negation Operator !` + +flips boolean condition of the expression. Equivalent of `bool(expr)==false` + +
+!true => 0 +!false => 1 +!null => 1 +!5 => 0 +!l() => 1 +!l(null) => 0 +diff --git a/docs/scarpet/language/Overview.md b/docs/scarpet/language/Overview.md new file mode 100644 index 00000000..a63629da --- /dev/null +++ b/docs/scarpet/language/Overview.md @@ -0,0 +1,276 @@ +# Fundamental components of `scarpet` programming language (towards version 1.7). + +Scarpet (a.k.a. Carpet Script, or Script for Carpet) is a programming language +designed to provide the ability to write custom programs to run within Minecraft +and interact with the world. + +The project was initially built based on the EvalEx project, however it now diverged +so far away from the original implementation, it would be hard to tell it without +this mention. EvalEx is a handy expression evaluator for Java, that allows to evaluate +simple mathematical and boolean expressions. For more information, +see: [EvalEx GitHub repository](https://github.com/uklimaschewski/EvalEx) + +This specification is divided into two sections: this one is agnostic to any +Minecraft related features and could function on its own, and CarpetExpression +for Minecraft specific routines and world manipulation functions. + +# Synopsis + +
+script run print('Hello World!')
+
+
+or an OVERLY complex example:
+
+
+/script run
+ block_check(x1, y1, z1, x2, y2, z2, block_to_check) ->
+ (
+ l(minx, maxx) = sort(l(x1, x2));
+ l(miny, maxy) = sort(l(y1, y2));
+ l(minz, maxz) = sort(l(z1, z2));
+ 'Need to compute the size of the area of course';
+ 'Cause this language doesn\'t support comments in the command mode';
+ xsize = maxx - minx + 1;
+ ysize = maxy - miny + 1;
+ zsize = maxz - minz + 1;
+ total_count = 0;
+ loop(xsize,
+ xx = minx + _ ;
+ loop(ysize,
+ yy = miny + _ ;
+ loop(zsize,
+ zz = minz + _ ;
+ if ( block(xx,yy,zz) == block_to_check,
+ total_count += ceil(rand(1))
+ )
+ )
+ )
+ );
+ total_count
+ );
+ check_area_around_closest_player_for_block(block_to_check) ->
+ (
+ closest_player = player();
+ l(posx, posy, posz) = query(closest_player, 'pos');
+ total_count = block_check( posx-8,1,posz-8, posx+8,17,posz+8, block_to_check);
+ print('There is '+total_count+' of '+block_to_check+' around you')
+ )
+/script invoke check_area_around_closest_player_for_block 'diamond_ore'
+
+
+or simply
+
+
+/script run print('There is'+for(rect(x,9,z,8,8,8), _ == 'diamond_ore')+' diamond ore around you')
+
+
+It definitely pays to check what higher level `scarpet` functions have to offer.
+
+# Programs
+
+You can think of an program like a mathematical expression, like `"2.4*sin(45)/(2-4)"` or `"sin(y)>0 & max(z, 3)>3"`.
+Writing a program, is like writing a `2+3`, just a bit longer.
+
+## Basic language components
+
+Programs consist of constants, like `2`, `3.14`, `pi`, or `'foo'`, operators like `+`, `/`, `->`, variables which you
+can define, like `foo` or special ones that will be defined for you, like `_x`, or `_` , which I specific to a each
+built in function, and functions with name, and arguments in the form of `f(a,b,c)`, where `f` is the function name,
+and `a, b, c` are the arguments which can be any other expression. And that's all the parts of the language, so all
+in all - sounds quite simple.
+
+## Code flow
+
+Like any other proper programming language, `scarpet` needs brackets, basically to identify where stuff begins and
+where it ends. In the languages that uses much more complicated constructs, like Java, they tend to use all sort of
+them, round ones to indicate function calls, curly to indicate section of code, square to access lists, pointy for
+generic types etc... I mean - there is no etc, cause they have exhausted all the bracket options...
+
+`Scarpet` is different, since it runs everything based on functions (although its not per se a functional
+language like lisp) only needs the round brackets for everything, and it is up to the programmer to organize
+its code so its readable, as adding more brackets does not have any effect on the performance of the programs
+as they are compiled before they are executed. Look at the following example usage of `if()` function:
+
+
+if(x<y+6,set(x,8+y,z,'air');plop(x,top('surface',x,z),z,'birch'),sin(query(player(),'yaw'))>0.5,plop(0,0,0,'boulder'),particle('fire',x,y,z))
+
+
+Would you prefer to read
+
+
+if( x<y+6,
+ set(x,8+y,z,'air');
+ plop(x,top('surface',x,z),z,'birch'),
+ sin(query(player(),'yaw'))>0.5,
+ plop(0,0,0,'boulder'),
+ particle('fire',x,y,z)
+)
+
+
+Or rather:
+
+
+if
+(
+ x<y+6,
+ (
+ set(x,8+y,z,'air');
+ plop(x,top('surface',x,z),z,'birch')
+ ),
+ sin(query(player(),'yaw'))>0.5,
+ (
+ plop(0,0,0,'boulder')
+ ),
+ particle('fire',x,y,z)
+)
+
+
+Whichever style you prefer it doesn't matter. It typically depends on the situation and the complexity of the
+subcomponents. No matter how many whitespaces and extra brackets you add - the code will evaluate to exactly the
+same expression, and will run exactly the same, so make sure your programs are nice and clean so others don't
+have problems with them
+
+## Functions and scoping
+
+Users can define functions in the form `fun(args....) -> expression` and they are compiled and saved for further
+execution in this but also subsequent calls of /script command. Functions can also be assigned to variables,
+passed as arguments, called with `call` function, but in most cases you would want to call them directly by
+name, in the form of `fun(args...)`. This means that once defined functions are saved with the world for
+further use. For variables, there are two types of them, global - which are shared anywhere in the code,
+and those are all which name starts with 'global_', and local variables which is everything else and those
+are only visible inside each function. This also means that all the parameters in functions are
+passed 'by value', not 'by reference'.
+
+## Outer variables
+
+Functions can still 'borrow' variables from the outer scope, by adding them to the function signature wrapped
+around built-in function `outer`. It adds the specified value to the function call stack so they behave exactly
+like capturing lambdas in Java, but unlike java captured variables don't need to be final. Scarpet will just
+attach their new values at the time of the function definition, even if they change later. Most value will be
+copied, but mutable values, like maps or lists, allow to keep the 'state' with the function, allowing them to
+have memory and act like objects so to speak. . Check `outer(var)` for details.
+
+## Code delivery, line indicators
+
+Note that this should only apply to pasting your code to execute with commandblock. Scarpet recommends placing
+your code in apps (files with `.sc` extension that can be placed inside "/scripts" folder in the world files and
+loaded as a scarpet app with command `/script load [app_name]`. Scarpet apps loaded from disk should only
+contain code, no need to start with "/script run" prefix
+
+The following is the code that could be provided in a `foo.sc` app file located in world `/scripts` folder
+
+
+run_program() -> (
+ loop( 10,
+ // looping 10 times
+ // comments are allowed in scripts located in world files
+ // since we can tell where that line ends
+ foo = floor(rand(10));
+ check_not_zero(foo);
+ print(_+' - foo: '+foo);
+ print(' reciprocal: '+ _/foo )
+ )
+);
+check_not_zero(foo) -> (
+ if (foo==0, foo = 1)
+)
+
+
+Which we then call in-game with:
+
++/script load foo +/script in foo invoke run_program ++ +However the following code can also be input as a command, or in a command block. + +Since the maximum command that can be input to the chat is limited in length, you will be probably inserting your +programs by pasting them to command blocks or reading from world files, however pasting to command blocks will +remove some whitespaces and squish your newlines making the code not readable. If you are pasting a program that +is perfect and will never cause an error, I salute you, but for the most part it is quite likely that your program +might break, either at compile time, when its initially analyzed, or at execute time, when you suddenly attempt to +divide something by zero. In these cases you would want to get a meaningful error message, but for that you would +need to indicate for the compiler where did you put these new lines, since command block would squish them. For that, +place at the beginning of the line to let the compiler know where are you. This makes so that `$` is the only +character that is illegal in programs, since it will be replaced with new lines. As far as I know, `$` is not +used anywhere inside Minecraft identifiers, so this shouldn't hinder the abilities of your programs. + +Consider the following program executed as command block command: + +
+/script run
+run_program() -> (
+ loop( 10,
+ foo = floor(rand(_));
+ check_not_zero(foo);
+ print(_+' - foo: '+foo);
+ print(' reciprocal: '+ _/foo )
+ )
+);
+check_not_zero(foo) -> (
+ if (foo==0, foo = 1)
+)
+
+
+Lets say that the intention was to check if the bar is zero and prevent division by zero in print, but because
+the `foo` is passed as a variable, it never changes the original foo value. Because of the inevitable division
+by zero, we get the following message:
+
+
+Your math is wrong, Incorrect number format for NaN at pos 98
+run_program() -> ( loop( 10, foo = floor(rand(_)); check_not_zero(foo); print(_+' - foo: '+foo);
+HERE>> print(' reciprocal: '+ _/foo ) ));check_not_zero(foo) -> ( if (foo==0, foo = 1))
+
+
+As we can see, we got our problem where the result of the mathematical operation was not a number
+(infinity, so not a number), however by pasting our program into the command made it squish the newlines so
+while it is clear where the error happened and we still can track the error down, the position of the error (98)
+is not very helpful and wouldn't be useful if the program gets significantly longer. To combat this issue we can
+precede every line of the script with dollar signs `$`:
+
+
+/script run
+$run_program() -> (
+$ loop( 10,
+$ foo = floor(rand(_));
+$ check_not_zero(foo);
+$ print(_+' - foo: '+foo);
+$ print(' reciprocal: '+ _/foo )
+$ )
+$);
+$check_not_zero(foo) -> (
+$ if (foo==0, foo = 1)
+$)
+
+
+Then we get the following error message
+
+
+Your math is wrong, Incorrect number format for NaN at line 7, pos 2
+ print(_+' - foo: '+foo);
+ HERE>> print(' reciprocal: '+ _/foo )
+ )
+
+
+As we can note not only we get much more concise snippet, but also information about the line number and position,
+so means its way easier to locate the potential problems problem
+
+Obviously that's not the way we intended this program to work. To get it `foo` modified via a function call,
+we would either return it as a result and assign it to the new variable:
+
++foo = check_not_zero(foo); +... +check_not_zero(foo) -> if(foo == 0, 1, foo) ++ +.. or convert it to a global variable, which in this case passing as an argument is not required + +
+global_foo = floor(rand(10)); +check_foo_not_zero(); +... +check_foo_not_zero() -> if(global_foo == 0, global_foo = 1) +\ No newline at end of file diff --git a/docs/scarpet/language/SystemFunctions.md b/docs/scarpet/language/SystemFunctions.md new file mode 100644 index 00000000..502a3c63 --- /dev/null +++ b/docs/scarpet/language/SystemFunctions.md @@ -0,0 +1,324 @@ +# System functions + +## Type conversion functions + +### `copy(expr)` + +Returns the deep copy of the expression. Can be used to copy mutable objects, like maps and lists + +### `type(expr)` + +Returns the string value indicating type of the expression. Possible outcomes +are `null, number, string, list, iterator`, as well as minecraft related concepts like `block, entity, nbt` + +### `bool(expr)` + +Returns a boolean context of the expression. Note that there are no true/false values in scarpet. `true` is +alias of 1, and `false` is 0\. Bool is also interpreting string values as boolean, which is different from other +places where boolean context can be used. This can be used in places where API functions return string values to +represent binary values + +
+bool(pi) => 1
+bool(false) => 0
+bool('') => 0
+bool(l()) => 0
+bool(l('')) => 1
+bool('foo') => 1
+bool('false') => 0
+bool('nulL') => 0
+if('false',1,0) => 1
+
+
+### `number(expr)`
+
+Returns a numeric context of the expression. Can be used to read numbers from strings
+
+
+number(null) => null
+number(false) => 0
+number('') => null
+number('3.14') => 3.14
+number(l()) => 0
+number(l('')) => 1
+number('foo') => null
+number('3bar') => null
+number('2')+number('2') => 4
+
+
+### `str(expr, params? ... ), str(expr, param_list)`
+
+Returns a formatted string representing expression. Accepts formatting style accepted by `String.format`.
+Supported types (with `"%?"` syntax):
+
+* d, o, x: integers
+* a, e, f, g: floats
+* b: booleans
+* s: strings
+
+
+str(null) => null
+str(false) => 0
+str('') => null
+str('3.14') => 3.14
+str(l()) => 0
+str(l('')) => 1
+str('foo') => null
+str('3bar') => null
+str(2)+str(2) => 22
+str('pi: %.2f',pi) => 'pi: 3.14'
+str('player at: %d %d %d',pos(player())) => 'player at: 567, -2423, 124'
+
+
+* * *
+## Threading and Parallel Execution
+
+Scarpet allows to run threads of execution in parallel to the main script execution thread. In Minecraft, the main
+thread scripts are executed on the main server thread. Since Minecraft is inherently NOT thread safe, it is not that
+beneficial to parallel execution in order to access world resources faster. Both `GetBlockState` and `setBlockState`
+are not thread safe and require the execution to park on the server thread, where these requests can be executed in
+the off-tick time in between ticks that didn't take 50ms. There are however benefits of running things in parallel,
+like fine time control not relying on the tick clock, or running things independent on each other. You can still run
+your actions on tick-by-tick basis, either taking control of the execution using `game_tick()` API function
+(nasty solution), or scheduling tick using `schedule()` function (much nicer solution), but threading often gives
+the neatest solution to solve problems in parallel (see scarpet camera).
+
+Due to limitations with the game, there are some limits to the threading as well. You cannot for
+instance `join_task()` at all from the main script and server thread, because any use of Minecraft specific
+function that require any world access, will require to park and join on the main thread to get world access,
+meaning that calling join on that task would inevitably lead to a typical deadlock. You can still join tasks
+from other threads, just because the only possibility of a deadlock in this case would come explicitly from your
+bad code, not the internal world access behaviour. Some things tough like player or entity manipulation, can be
+effectively parallelized.
+
+### `task(function, ?args...., ?executor)`
+
+Creates and runs a parallel task, returning the handle to the task object. Task will return the return value of the
+function when its completed, or will return `null` immediately if task is still in progress, so grabbing a value of
+a task object is non-blocking. Function can be either function value, or function lambda, or a name of an existing
+defined function. In case function needs arguments to be called with, they should be supplied after the function
+name, or value. Optional `executor` identifier is to place the task in a specific queue identified by this value.
+The default thread value is the `null` thread. There is no limits on number of parallel tasks for any executor,
+so using different queues is solely for synchronization purposes. Also, since `task` function knows how many extra
+arguments it requires, the use of tailing optional parameter for the custom executor thread pool is not ambiguous.
+
+
+task( _() -> print('Hello Other World') ) => Runs print command on a separate thread
+foo(a, b) -> print(a+b); task('foo',2,2) => Uses existing function definition to start a task
+task('foo',3,5,'temp'); => runs function foo with a different thread executor, identified as 'temp'
+a = 3; task( _(outer(a), b) -> foo(a,b), 5, 'temp')
+ => Another example of running the same thing passing arguments using closure over anonymous function as well as passing a parameter.
+
+
+### `task_count(executor?)`
+
+If no argument provided, returns total number of tasks being executed in parallel at this moment using scarpet
+threading system. If the executor is provided, returns number of active tasks for that provider. Use `task_count(null)`
+to get the task count of the default executor only.
+
+### `task_value(task)`
+
+Returns the task return value, or `null` if task hasn't finished yet. Its a non-blocking operation. Unlike `join_task`,
+can be called on any task at any point
+
+### `task_join(task)`
+
+Waits for the task completion and returns its computed value. If the task has already finished returns it immediately.
+Unless taking the task value directly, i.e. via `task_value`, this operation is blocking. Since Minecraft has a
+limitation that all world access operations have to be performed on the main game thread in the off-tick time,
+joining any tasks that use Minecraft API from the main thread would mean automatic lock, so joining from the main
+thread is not allowed. Join tasks from other threads, if you really need to, or communicate asynchronously with
+the task via globals or function data / arguments to monitor its progress, communicate, get partial results,
+or signal termination.
+
+### `task_completed(task)`
+
+Returns true if task has completed, or false otherwise.
+
+### `synchronize(lock, expression)`
+
+Evaluates `expression` synchronized with respect to the lock `lock`. Returns the value of the expression.
+
+* * *
+
+## Auxiliary functions
+
+### `lower(expr), upper(expr), title(expr)`
+
+Returns lowercase, uppercase or titlecase representation of a string representation of the passed expression
+
+
+lower('aBc') => 'abc'
+upper('aBc') => 'ABC'
+title('aBc') => 'Abc'
+
+
+### `replace(string, regex, repl?); replace_first(string, regex, repl?)`
+
+Replaces all, or first occurence of a regular expression in the string with `repl` expression,
+or nothing, if not specified
+
+
+replace('abbccddebfg','b+','z') // => azccddezfg
+replace_first('abbccddebfg','b+','z') // => azccddebfg
+
+
+### `length(expr)`
+
+Returns length of the expression, the length of the string, the length of the integer part of the number,
+or length of the list
+
+
+length(pi) => 1
+length(pi*pi) => 1
+length(pi^pi) => 2
+length(l()) => 0
+length(l(1,2,3)) => 3
+length('') => 0
+length('foo') => 3
+
+
+### `rand(expr), rand(expr, seed)`
+
+returns a random number from `0.0` (inclusive) to `expr` (exclusive). In boolean context (in conditions,
+boolean functions, or `bool`), returns false if the randomly selected value is less than 1\. This means
+that `rand(2)` returns true half of the time and `rand(5)` returns true for 80% (4/5) of the time. If seed is not
+provided, uses a random seed. If seed is provided, each consecutive call to rand() will act like 'next' call to the
+same random object. Scarpet keeps track of up to 1024 custom random number generators, so if you exceed this number
+(per app), then your random sequence will revert to the beginning.
+
+
+map(range(10), floor(rand(10))) => [5, 8, 0, 6, 9, 3, 9, 9, 1, 8]
+map(range(10), bool(rand(2))) => [1, 1, 1, 0, 0, 1, 1, 0, 0, 0]
+map(range(10), str('%.1f',rand(_))) => [0.0, 0.4, 0.6, 1.9, 2.8, 3.8, 5.3, 2.2, 1.6, 5.6]
+
+
+### `perlin(x), perlin(x, y), perlin(x, y, z), perlin(x, y, z, seed)`
+
+returns a noise value from `0.0` to `1.0` (roughly) for 1, 2 or 3 dimensional coordinate. The default seed it samples
+from is `0`, but seed can be specified as a 4th argument as well. In case you need 1D or 2D noise values with custom
+seed, use `null` for `z`, or `y` and `z` arguments respectively.
+
+Perlin noise is based on a square grid and generates rougher maps comparing to Simplex, which is creamier.
+Querying for lower-dimensional result, rather than affixing unused dimensions to constants has a speed benefit,
+
+Thou shall not sample from noise changing seed frequently. Scarpet will keep track of the last 256 perlin seeds
+used for sampling providing similar speed comparing to the default seed of `0`. In case the app engine uses more
+than 256 seeds at the same time, switching between them can get much more expensive.
+
+### `simplex(x, y), simplex(x, y, z), simplex(x, y, z, seed)`
+
+returns a noise value from `0.0` to `1.0` (roughly) for 2 or 3 dimensional coordinate. The default seed it samples
+from is `0`, but seed can be specified as a 4th argument as well. In case you need 2D noise values with custom seed,
+use `null` for `z` argument.
+
+Simplex noise is based on a triangular grid and generates smoother maps comparing to Perlin. To sample 1D simplex
+noise, affix other coordinate to a constant.
+
+Thou shall not sample from noise changing seed frequently. Scarpet will keep track of the last 256 simplex seeds
+used for sampling providing similar speed comparing to the default seed of `0`. In case the app engine uses more
+than 256 seeds at the same time, switching between them can get much more expensive.
+
+### `print(expr)`
+
+prints the value of the expression to chat. Passes the result of the argument to the output unchanged,
+so `print`-statements can be weaved in code to debug programming issues
+
+
+print('foo') => results in foo, prints: foo
+a = 1; print(a = 5) => results in 5, prints: 5
+a = 1; print(a) = 5 => results in 5, prints: 1
+print('pi = '+pi) => prints: pi = 3.141592653589793
+print(str('pi = %.2f',pi)) => prints: pi = 3.14
+
+
+### `sleep(expr)`
+
+Halts the execution of the program (and the game itself) for `expr` milliseconds. All in all, its better to
+use `game_tick(expr)` to let the game do its job while the program waits
+
++sleep(50) ++ +### `time()` + +Returns the number of milliseconds since 'some point', like Java's `System.nanoTime()`. +It returns a float, which has 1 microsecond precision (0.001 ms) + +
+start_time = time();
+flip_my_world_upside_down();
+print(str('this took %d milliseconds',time()-start_time))
+
+
+### `profile_expr(expression)`
+
+Returns number of times given expression can be run in 50ms time. Useful to profile and optimize your code.
+Note that, even if its only a number, it WILL run these commands, so if they are destructive, you need to be careful.
+
+* * *
+
+## Access to variables and stored functions (use with caution)
+
+### `var(expr)`
+
+Returns the variable under the name of the string value of the expression. Allows to manipulate variables in more
+programmatic manner, which allows to use local variable set with a hash map type key-value access,
+can also be used with global variables
+
+
+a = 1; var('a') = 'foo'; a => a == 'foo'
+
+
+### `undef(expr)`
+
+Removes all bindings of a variable with a name of `expr`. Removes also all function definitions with that name.
+It can affect global variable pool, and local variable set for a particular function.
+
+
+inc(i) -> i+1; foo = 5; inc(foo) => 6
+inc(i) -> i+1; foo = 5; undef('foo'); inc(foo) => 1
+inc(i) -> i+1; foo = 5; undef('inc'); undef('foo'); inc(foo) => Error: Function inc is not defined yet at pos 53
+undef('pi') => bad idea - removes hidden variable holding the pi value
+undef('true') => even worse idea, unbinds global true value, all references to true would now refer to the default 0
+
+
+### `vars(prefix)`
+
+It returns all names of variables from local scope (if prefix does not start with 'global') or global variables
+(otherwise). Here is a larger example that uses combination of `vars` and `var` functions to be
+used for object counting
+
+
+/script run
+$ count_blocks(ent) -> (
+$ l(cx, cy, cz) = query(ent, 'pos');
+$ scan(cx, cy, cz, 16, 16, 16, var('count_'+_) += 1);
+$ for ( sort_key( vars('count_'), -var(_)),
+$ print(str( '%s: %d', slice(_,6), var(_) ))
+$ )
+$ )
+/script run count_blocks(player())
+
+
+* * *
+
+## System key-value storage
+
+Scarpet runs apps in isolation. The can share code via use of shared libraries, but each library that is imported to
+each app is specific to that app. Apps can store and fetch state from disk, but its restricted to specific locations
+meaning apps cannot interact via disk either. To facilitate communication for interappperability, scarpet hosts its
+own key-value storage that is shared between all apps currently running on the host, providing methods for getting an
+associated value with optional setting it if not present, and an operation of modifying a content of a system
+global value.
+
+### `system_variable_get(key, default_value ?)`
+
+Returns the variable from the system shared key-value storage keyed with a `key` value, optionally if value is
+not present, and default expression is provided, sets a new value to be associated with that key
+
+### `system_variable_set(key, new_value)`
+
+Returns the variable from the system shared key-value storage keyed with a `key` value, and sets a new
+mapping for the key
\ No newline at end of file
diff --git a/docs/scarpet/language/VariablesAndConstants.md b/docs/scarpet/language/VariablesAndConstants.md
new file mode 100644
index 00000000..e3478327
--- /dev/null
+++ b/docs/scarpet/language/VariablesAndConstants.md
@@ -0,0 +1,29 @@
+# Variables and Constants
+
+`scarpet` provides a number of constants that can be used literally in scripts
+
+* `null`: nothing, zilch, not even false
+* `true`: pure true, or just 1 (one)
+* `false`: false truth, or true falsth, 0 (zero) actually
+* `pi`: for the fans of perimeters, its a perimeter of an apple pi of diameter 1\. About 3.14
+* `euler`: clever guy. Derivative of its exponent is goto 1\. About 2.72
+
+Apart from that, there is a bunch of system variables, that start with `_` that are set by `scarpet` built-ins,
+like `_`, typically each consecutive value in loops, `_i` indicating iteration, or `_a` like an accumulator
+for `reduce` function. Certain calls to Minecraft specific calls would also set `_x`, `_y`, `_z`, indicating
+block positions. All variables starting with `_` are read-only, and cannot be declared and modified in client code.
+
+## Literals
+
+`scarpet` accepts numeric and string liters constants. Numbers look like `1, 2.5, -3e-7, 0xff,` and are internally
+represented as Java's `double` but `scarpet` will try to trim trailing zeros as much as possible so if you need to
+use them as intergers, you can. Strings using single quoting, for multiple reasons, but primarily to allow for
+easier use of strings inside doubly quoted command arguments (when passing a script as a parameter of `/script fill`
+for example, or when typing in jsons inside scarpet to feed back into a `/data merge` command for example.
+Strings also use backslashes `\` for quoting special characters, in both plain strings and regular expressions
+
+
+'foo'
+print('This doesn\'t work')
+nbt ~ '\\.foo' // matching '.' as a '.', not 'any character match'
+
diff --git a/src/main/java/carpet/script/CarpetExpression.java b/src/main/java/carpet/script/CarpetExpression.java
index 36160a64..411fc046 100644
--- a/src/main/java/carpet/script/CarpetExpression.java
+++ b/src/main/java/carpet/script/CarpetExpression.java
@@ -133,21 +133,6 @@ import static java.lang.Math.max;
import static java.lang.Math.min;
import static java.lang.Math.sqrt;
-/**
- * scarpet language add-ons and commandsHere is the gist of the Minecraft related functions. Otherwise the CarpetScript could live without Minecraft.
- *One note, which is important is that most of the calls for entities and blocks
- * would refer to the current dimension of the caller, meaning, that if we for example
- * list all the players using player('all') function, if a player is in the
- * other dimension, calls to entities and blocks around that player would point incorrectly.
- * Moreover, running commandblocks in the spawn chunks would mean that commands will always
- * refer to the overworld blocks and entities.
- * In case you would want to run commands across all dimensions, just run three of them, using
- * /execute in overworld/the_nether/the_end run script run ... and query
- * players using player('*'), which only returns players in current dimension, or use
- * in_dimension(expr) function.
script stop/script resume command
- * /script stop allows to stop execution of any script currently running that calls the
- * game_tick() function which
- * allows the game loop to regain control of the game and process other commands. This will also make sure
- * that all current and future programs will stop their execution. Execution of all programs will be
- * prevented until /script resume command is called.
- *
Lets look at the following example. This is a program computes Fibonacci number in a recursive manner:
- *- * fib(n) -> if(n<3, 1, fib(n-1)+fib(n-2) ); fib(8) - *- *
That's really bad way of doing it, because the higher number we need to compute the compute requirements will rise
- * exponentially with n. It takes a little over 50 milliseconds to do fib(24), so above one tick,
- * but about a minute to do fib(40). Calling fib(40) will not only freeze the game, but also you woudn't be able to interrupt
- * its execution. We can modify the script as follows
fib(n) -> ( game_tick(50); if(n<3, 1, fib(n-1)+fib(n-2) ) ); fib(40)- *
But this would never finish as such call would finish after ~ 2^40 ticks. To make our computations
- * responsive, yet able to respond to user interactions, other commands, as well as interrupt execution,
- * we could do the following:
fib(n) -> ( if(n==23, game_tick(50) ); if(n<3, 1, fib(n-1)+fib(n-2) ) ); fib(40)- *
This would slow down the computation of fib(40) from a minute to two, but allows the game to keep continue running
- * and be responsive to commands, using about half of each tick to advance the computation.
- * Obviously depending on the problem, and available hardware, certain things can take
- * more or less time to execute, so portioning of work with calling gametick should be balanced in each
- * case separately
block(x, y, z), block(l(x,y,z)), block(state)Returns either a block from specified location, or block with a specific state
- * (as used by /setblock command), so allowing for block properties, block entity data etc.
- * Blocks otherwise can be referenced everywhere by its simple string name, but its only used in its default state
- * block('air') => air
- * block('iron_trapdoor[half=top]') => iron_trapdoor
- * block(0,0,0) == block('bedrock') => 1
- * block('hopper[facing=north]{Items:[{Slot:1b,id:"minecraft:slime_ball",Count:16b}]}') => hopper
- *
- * Retrieving a block with block function has also a side-effect of evaluating its current state and data.
- * so if you use it later it will reflect block state and data of the block that was when block was called, rather than
- * when it was used. Block values passed in various places like scan functions, etc, are not fully evaluated
- * unless its properties are needed. This means that if the block at the location changes before its queried in the program
- * this might result in getting the later state, which might not be desired. Consider the following example:
- * set(10,10,10,'stone'); - * scan(10,10,10,0,0,0, b = _); - * set(10,10,10,'air'); - * print(b); // 'air', block was remembered 'lazily', and evaluated by `print`, when it was already set to air - * - * set(10,10,10,'stone'); - * scan(10,10,10,0,0,0, b = block(_)); - * set(10,10,10,'air'); - * print(b); // 'stone', block was evaluated 'eagerly' but call to `block` - * - *- *
All the functions below can be used with block value, queried with coord triple, or 3-long list.
- * All pos in the functions referenced below refer to either method of passing block position
set(pos, block, property?, value?, ...)First part of the set function is either a coord triple, list of three numbers, or other block
- * with coordinates. Second part, block is either block value as a result of block() function
- * string value indicating the block name, and optional property - value pairs for extra block properties.
- * If block is specified only by name, then if a destination block is the same the set operation
- * is skipped, otherwise is executed, for other potential extra properties
The returned value is either the block state that has been set, or false if block setting was skipped
- * set(0,5,0,'bedrock') => bedrock
- * set(l(0,5,0), 'bedrock') => bedrock
- * set(block(0,5,0), 'bedrock') => bedrock
- * scan(0,5,0,0,0,0,set(_,'bedrock')) => 1
- * set(pos(players()), 'bedrock') => bedrock
- * set(0,0,0,'bedrock') => 0 // or 1 in overworlds generated in 1.8 and before
- * scan(0,100,0,20,20,20,set(_,'glass'))
- * // filling the area with glass
- * scan(0,100,0,20,20,20,set(_,block('glass')))
- * // little bit faster due to internal caching of block state selectors
- * b = block('glass'); scan(0,100,0,20,20,20,set(_,b))
- * // yet another option, skips all parsing
- * set(x,y,z,'iron_trapdoor') // sets bottom iron trapdoor
- * set(x,y,z,'iron_trapdoor[half=top]') // Incorrect. sets bottom iron trapdoor - no parsing of properties
- * set(x,y,z,'iron_trapdoor','half','top') // correct - top trapdoor
- * set(x,y,z,block('iron_trapdoor[half=top]')) // also correct, block() provides extra parsing
- * set(x,y,z,'hopper[facing=north]{Items:[{Slot:1b,id:"minecraft:slime_ball",Count:16b}]}') // extra block data
- *
- * without_updates(expr)Evaluates subexpression without causing updates when blocks change in the world
- *Consider following scenario: We would like to generate a bunch of terrain in a flat world - * following a perling noise generator. The following code causes cascading effect as blocks placed on chunk borders will - * cause other chunks to get loaded to full, thus generated:
- *
- * __config() -> m(l('scope', 'global'));
- * __on_chunk_generated(x, z) -> (
- * scan(x,0,z,0,0,0,15,15,15,
- * if (perlin(_x/16, _y/8, _z/16) > _y/16,
- * set(_, 'black_stained_glass');
- * )
- * )
- * )
- *
- * The following addition resolves this issue, by not allowing block updates pass chunk borders:
- *
- * __config() -> m(l('scope', 'global'));
- * __on_chunk_generated(x, z) -> (
- * without_updates(
- * scan(x,0,z,0,0,0,15,15,15,
- * if (perlin(_x/16, _y/8, _z/16) > _y/16,
- * set(_, 'black_stained_glass');
- * )
- * )
- * )
- * )
- *
- * place_item(item, pos, facing?, sneak?)Places a given item in the world like it was placed by a player. Item names are default minecraft item name, - * less the minecraft prefix. Default facing is 'up', but there are other options: 'down', 'north', 'east', - * 'south', 'west', but also there are other secondary directions important for placement of blocks like stairs, doors, etc. - * Try experiment with options like 'north-up' which is placed facing north with cursor pointing to the upper part of the block, - * or 'up-north', which means a block placed facing up (player looking down) and placed smidge away of the block center - * towards north. Optional sneak is a boolean indicating if a player would be sneaking while placing the block - - * this option only affects placement of chests and scaffolding at the moment. - * Returns true if placement was successful, false otherwise.
- *
- * place_item('stone',x,y,z) // places a stone block on x,y,z block
- * place_item('piston,x,y,z,'down') // places a piston facing down
- * place_item('carrot',x,y,z) // attempts to plant a carrot plant. Returns true if could place carrots at that position.
- *
- * set_poi(pos, type, occupancy?)Sets a Point of Interest (POI) of a specified type with optional custom occupancy. By default new POIs are not
- * occupied. If type is null, POI at position is removed. In any case, previous POI is also removed.
- * Available POI types are:
'unemployed', 'armorer', 'butcher', 'cartographer', 'cleric', 'farmer', 'fisherman', 'fletcher', 'leatherworker',
- * 'librarian', 'mason', 'nitwit', 'shepherd', 'toolsmith', 'weaponsmith', 'home', 'meeting', 'beehive', 'bee_nest', 'nether_portal'Interestingly, unemployed, and nitwit are not used in the game, meaning, they could be used
- * as permanent spatial markers for scarpet apps. meeting is the only one with increased max occupancy of 32.
set_biome(pos, biome_name)changes biome at that block position.
- *update(pos)Causes a block update at position.
- *block_tick(pos)Causes a block to tick at position.
- *random_tick(pos)Causes a random tick at position.
- *destroy(pos), destroy(pos, -1), destroy(pos, <N>), destroy(pos, tool, nbt?)Destroys the block like it was mined by a player. Add -1 for silk touch, and positive number for fortune level. - * If tool is specified, and optionally its nbt, it will use that tool and will attempt to mine the block with this tool. - * If called without item context, this function, unlike harvest, will affect all kinds of blocks. If called with item in context, - * it will fail to break blocks that cannot be broken by a survival player.
- *Without item context it returns false if failed to destroy the block and true if block breaking was
- * successful. In item context, true means that breaking item has no nbt to use, null indicating that
- * the tool should be considered broken in process, and nbt type value, for a resulting NBT tag on a hypothetical tool.
- * Its up to the programmer to use that nbt to apply it where it belong
- *
Here is a sample code that can be used to mine blocks using items in player inventory, without using player context for mining.
- * Obviously, in this case the use of harvest would be much more applicable:
- * mine(x,y,z) ->
- * (
- * p = player();
- * slot = p~'selected_slot';
- * item_tuple = inventory_get(p, slot);
- * if (!item_tuple, destroy(x,y,z,'air'); return()); // empty hand, just break with 'air'
- * l(item, count, tag) = item_tuple;
- * tag_back = destroy(x,y,z, item, tag);
- * if (tag_back == false, // failed to break the item
- * return(tag_back)
- * );
- * if (tag_back == true, // block broke, tool has no tag
- * return(tag_back)
- * );
- * if (tag_back == null, //item broke
- * delete(tag:'Damage');
- * inventory_set(p, slot, count-1, item, tag);
- * return(tag_back)
- * );
- * if (type(tag_back) == 'nbt', // item didn't break, here is the effective nbt
- * inventory_set(p, slot, count, item, tag_back);
- * return(tag_back)
- * );
- * print('How did we get here?');
- * )
- *
- * harvest(player, pos)Causes a block to be harvested by a specified player entity. Honors player item enchantments, as well as damages the - * tool if applicable. If the entity is not a valid player, no block gets destroyed. If a player is not allowed to - * break that block, a block doesn't get destroyed either.
- * - *pos(block), pos(entity)Returns a triple of coordinates of a specified block or entity. Technically entities are queried with
- * query function and the same can be achieved with query(entity,'pos'), but for simplicity
- * pos allows to pass all positional objects.
- * pos(block(0,5,0)) => l(0,5,0)
- * pos(players()) => l(12.3, 45.6, 32.05)
- * pos(block('stone')) => Error: Cannot fetch position of an unrealized block
- *
- * pos_offset(pos, direction, amount?)Returns a coords triple that is offset in a specified direction by amount of blocks.
- * The default offset amount is 1 block. To offset into opposite facing, use negative numbers for the amount.
- *
- * pos_offset(block(0,5,0), 'up', 2) => l(0,7,0) - * pos_offset(l(0,5,0), 'up', -2 ) => l(0,3,0) - *- *
block_properties(pos)Returns a list of available block properties for a particular block. If a block has no properties, returns an empty list.
- *property(pos, name)Returns property of block at pos, or specified by block argument. If a block doesn't
- * have that property, null value is returned. Returned values are always strings. It is expected from
- * the user to know what to expect and convert values to numbers using number() function or booleans
- * using bool() function.
- * set(x,y,z,'iron_trapdoor','half','top'); property(x,y,z,'half') => top
- * set(x,y,z,'air'); property(x,y,z,'half') => null
- * property(block('iron_trapdoor[half=top]'),'half') => top
- * property(block('iron_trapdoor[half=top]'),'powered') => false
- * bool(property(block('iron_trapdoor[half=top]'),'powered')) => 0
- *
- * block_data(pos)Return NBT string associated with specific location, or null if the block does not carry block data. - * Can be currently used to match specific information from it, or use it to copy to another block
- *
- * block_data(x,y,z) => '{TransferCooldown:0,x:450,y:68, ... }'
- *
- * poi(pos), poi(pos, radius), poi(pos, radius, status)Queries a POI (Point of Interest) at a given position, returning null if none is found, or tuple of
- * poi type and its occupancy load. With optional radius and status, returns a list of POIs
- * around pos within a given radius. If status is specified (either 'available',
- * or 'occupied') returns only POIs with that status. The return format is again, poi type, occupancy load, and extra tripple of
- * coordinates.
Querying for POIs using the radius is intended use of POI mechanics and ability of accessing individual POIs via
- * poi(pos) in only provided for completness.
- * poi(x,y,z) => null // nothing set at position - * poi(x,y,z) => ['meeting',3] // its a bell-type meeting point occupied by 3 villagers - * poi(x,y,z,5) => [] // nothing around - * poi(x,y,z,5) => [['nether_portal',0,[7,8,9]],['nether_portal',0,[7,9,9]]] // two portal blocks in the range - *- *
biome(pos)returns biome at that block position.
- *solid(pos)Boolean function, true if the block is solid
- *air(pos)Boolean function, true if a block is air.... or cave air... - * or void air.... or any other air they come up with.
- *liquid(pos)Boolean function, true if the block is liquid, or liquidlogged
- *flammable(pos)Boolean function, true if the block is flammable
- *transparent(pos)Boolean function, true if the block is transparent
- *opacity(pos)Numeric, returning opacity level of a block
- *blocks_daylight(pos)Boolean function, true if the block blocks daylight
- *emitted_light(pos)Numeric, returning light level emitted from block
- *light(pos)Integer function, returning total light level at position
- *block_light(pos)Integer function, returning block light at position. From torches and other light sources.
- *sky_light(pos)Numeric function, returning sky light at position. From the sky access.
- *see_sky(pos)Boolean function, returning true if the block can see sky.
- *hardness(pos)Numeric function, indicating hardness of a block.
- *blast_resistance(pos)Numeric function, indicating blast_resistance of a block.
- *in_slime_chunk(pos)Boolean indicating if the given block position is in a slime chunk.
- - *top(type, pos)Returns the Y value of the topmost block at given x, z coords (y value of a block is not important), according to the
- * heightmap specified by type. Valid options are:
light: topmost light blocking block (1.13 only)motion: topmost motion blocking blockterrain: topmost motion blocking block except leavesocean_floor: topmost non-water blocksurface: topmost surface block
- * top('motion', x, y, z) => 63
- * top('ocean_floor', x, y, z) => 41
- *
- * loaded(pos)Boolean function, true if the block is accessible for the game mechanics.
- * Normally scarpet doesn't check if operates on
- * loaded area - the game will automatically load missing blocks. We see this as advantage.
- * Vanilla fill/clone commands only check the specified corners for loadness.
To check if block is truly loaded, I mean in memory, use generation_status(x) != null, as
- * chunks can still be loaded outside of the playable area, just are not used any of the game mechanics processes.
- * loaded(pos(players())) => 1 - * loaded(100000,100,1000000) => 0 - *- *
(Deprecated) loaded_ep(pos)Boolean function, true if the block is loaded and entity processing, as per 1.13.2
- *Deprecated as of scarpet 1.6, use loaded_status(x) > 0, or
- * just loaded(x) with the same effect
loaded_status(pos)Returns loaded status as per new 1.14 chunk ticket system, 0 for inaccessible, 1 for border chunk, - * 2 for ticking, 3 for entity ticking
- *generation_status(pos), generation_status(pos, true)Returns generation status as per new 1.14 chunk ticket system. Can return any value from several available
- * but chunks can only be valid in a few states: full, features, liquid_carvers,
- * and structure_starts. Returns null if the chunk is not in memory unless called with optional
- * true.
structures(pos), structures(pos, structure_name)Returns structure information for a given block position. Note that structure information is the same for
- * all the blocks from the same chunk. structures function can be called with a block, or a block and
- * a structure name. In the first case it returns a map of structures at a given position, keyed by structure name,
- * with values indicating the bounding box of the structure - a pair of two 3-value coords (see examples). When
- * called with an extra structure name, returns list of components for that structure, with their name, direction
- * and two sets of coordinates indicating the bounding box of the structure piece.
structure_references(pos), structure_references(pos, structure_name)Returns structure information that a chunk with a given block position is part of.
- * structure_references function can be called with a block, or a block and
- * a structure name. In the first case it returns a list of structure names that give chunk belongs to. When
- * called with an extra structure name, returns list of positions pointing to the lowest block position in chunks that
- * hold structure starts for these structures. You can query that chunk structures then to get its bounding boxes.
set_structure(pos, structure_name), set_structure(pos, structure_name, null)Creates or removes structure information of a structure associated with a chunk of pos.
- * Unlike plop, blocks are not placed in the world, only structure information is set. For the game this is a fully
- * functional structure even if blocks are not set. To remove structure a given point is in,
- * use structure_references to find where current structure starts.
suffocates(pos)Boolean function, true if the block causes suffocation.
- *power(pos)Numeric function, returning redstone power level at position.
- *ticks_randomly(pos)Boolean function, true if the block ticks randomly.
- *blocks_movement(pos)Boolean function, true if block at position blocks movement.
- *block_sound(pos)Returns the name of sound type made by the block at position. One of:
- *wood gravel grass stone metal glass wool sand snow ladder anvil slime sea_grass coral material(pos)Returns the name of material of the block at position. very useful to target a group of blocks. One of:
- * air void portal carpet plant water_plant vine sea_grass water bubble_column lava snow_layer fire redstone_bits cobweb redstone_lamp clay dirt grass packed_ice sand sponge wood wool tnt leaves glass ice cactus stone iron snow anvil barrier piston coral gourd dragon_egg cake map_colour(pos)Returns the map colour of a block at position. One of:
- * air grass sand wool tnt ice iron foliage snow clay dirt stone water wood quartz adobe magenta light_blue yellow lime pink gray light_gray cyan purple blue brown green red black gold diamond lapis emerald obsidian netherrack white_terracotta orange_terracotta magenta_terracotta light_blue_terracotta yellow_terracotta lime_terracotta pink_terracotta gray_terracotta light_gray_terracotta cyan_terracotta purple_terracotta blue_terracotta brown_terracotta green_terracotta red_terracotta black_terracotta Most functions in this category require inventory as the first argument. Inventory could be specified by
- * an entity, or a block, or position (three coordinates) of a potential block with inventory. Player enderchest inventory
- * require two arguments, keyword 'enderchest', followed by the player entity argument.
- * If the entity or a block doesn't
- * have an inventory, they typically do nothing and return null.
Most items returned are in the form of - * a triple of item name, count, and nbt or the extra data associated with an item. - * Manipulating of the nbt data can be costly, but retrieving them from the tuple to match other aspects is cheap
- *stack_limit(item)Returns number indicating what is the stack limit for the item. Its typically 1 (non-stackable), - * 16 (like buckets), or 64 - rest. It is recommended to consult this, as other inventory API functions - * ignore normal stack limits, and it is up to the programmer to keep it at bay. As of 1.13, game checks for negative - * numbers and setting an item to negative is the same as empty.
- *
- * stack_limit('wooden_axe') => 1
- * stack_limit('ender_pearl') => 16
- * stack_limit('stone') => 64
- *
- * item_category(item)Returns the string representing the category of a given item, like `building_blocks`, `combat`, or `tools`.
- *
- * item_category('wooden_axe') => tools
- * item_category('ender_pearl') => misc
- * item_category('stone') => building_blocks
- *
- * inventory_size(inventory)Returns the size of the inventory for the entity or block in question. Returns null if the block or entity - * don't have an inventory
- *
- * inventory_size(player()) => 41
- * inventory_size('enderchest', player()) => 27 // enderchest
- * inventory_size(x,y,z) => 27 // chest
- * inventory_size(block(pos)) => 5 // hopper
- *
- * inventory_has_items(inventory)Returns true, if the inventory is not empty, false if it is empty, and null, if its not an inventory.
- *- * inventory_has_items(player()) => true - * inventory_has_items(x,y,z) => false // empty chest - * inventory_has_items(block(pos)) => null // stone - *- *
inventory_get(inventory, slot)Returns the item in the corresponding inventory slot, or null if slot empty or inventory is invalid. - * You can use negative numbers to indicate slots counted from 'the back'.
- *
- * inventory_get(player(), 0) => null // nothing in first hotbar slot
- * inventory_get(x,y,z, 5) => ['stone', 1, {}]
- * inventory_get(player(), -1) => ['diamond_pickaxe', 1, {Damage:4}] // slightly damaged diamond pick in the offhand
- *
- *
- * inventory_set(inventory, slot, count, item?, nbt?) Modifies or sets a stack in inventory. specify count 0 to empty the slot. - * If item is not specified, keeps existing item, just modifies the count. If item is provided - replaces current item. - * If nbt is provided - adds a tag to the stack at slot. Returns previous stack in that slot.
- *
- * inventory_set(player(), 0, 0) => ['stone', 64, {}] // player had a stack of stone in first hotbar slot
- * inventory_set(player(), 0, 6) => ['diamond', 64, {}] // changed stack of diamonds in player slot to 6
- * inventory_set(player(), 0, 1, 'diamond_axe','{Damage:5}') => null //added slightly damaged pick to first player slot
- *
- *
- * inventory_find(inventory, item, start_slot?, ), inventory_find(inventory, null, start_slot?) Finds the first slot with a corresponding item in the inventory, or if queried with null: the first empty slot. - * Returns slot number if found, or null otherwise. Optional start_slot argument allows to skip all preceeding slots - * allowing for efficient (so not slot-by-slot) inventory search for items.
- *- * inventory_find(player(), 'stone') => 0 // player has stone in first hotbar slot - * inventory_find(player(), null) => null // player's inventory has no empty spot - * while( (slot = inventory_find(p, 'diamond', slot)) != null, 41, drop_item(p, slot) ) - * // spits all diamonds from player inventory wherever they are - * inventory_drop(x,y,z, 0) => 64 // removed and spawned in the world a full stack of items - *- * - *
inventory_remove(inventory, item, amount?) Removes amount (defaults to 1) of item from inventory. If the inventory doesn't have the defined amount, nothing - * happens, otherwise the given amount of items is removed wherever they are in the inventory. Returns boolean whether - * the removal operation was successful. Easiest way to remove a specific item from player inventory without specifying - * the slot.
- *- * inventory_remove(player(), 'diamond') => 1 // removed diamond from player inventory - * inventory_remove(player(), 'diamond', 100) => 0 // player doesn't have 100 diamonds, nothing happened - *- * - *
drop_item(inventory, slot, amount?, )Drops the items from indicated inventory slot, like player that Q's an item or villager, that exchanges food. - * You can Q items from block inventories as well. default amount is 0 - which is all from the slot. NOTE: hoppers are quick - * enough to pick all the queued items from their inventory anyways. - * Returns size of the actual dropped items.
- *- * inventory_drop(player(), 0, 1) => 1 // Q's one item on the ground - * inventory_drop(x,y,z, 0) => 64 // removed and spawned in the world a full stack of items - *- *
Entities have to be fetched before using them. Entities can also change their state between calls to the script
- * if game happens either in between separate calls to the programs, or if the program calls game_tick
- * on its own. In this case - entities would need to be re-fetched, or the code should account for entities getting dead
player(), player(type), player(name)
- * With no arguments, it returns the calling player or the player closest to the caller. Note that the main context
- * will receive p variable pointing to this player. With type or name specified
- * it will try first to match a type, returning a list of players matching a type, and if this fails, will assume its
- * player name query retuning player with that name, or null if no player was found.
- * With 'all', list of all players in the game, in all dimensions, so end user needs to be cautious, that
- * you might be referring to wrong blocks and entities around the player in question.
- * WIth type = '*' it returns all players in caller dimension, 'survival' returns all survival
- * and adventure players, 'creative' returns all creative players, 'spectating' returns all spectating
- * players, and '!spectating', all not-spectating players. If all fails,
- * with name, the player in question, if is logged in.
entity_id(uuid), entity_id(id)Fetching entities wither by their ID obtained via entity ~ 'id', which is unique
- * for a dimension and current world run, or by UUID, obtained via entity ~ 'uuid'.
- * It returns null if no such entity
- * is found. Safer way to 'store' entities between calls, as missing entities will be returning null.
- * Both calls using UUID or numerical ID are O(1), but obviously using UUIDs takes more memory and compute.
entity_list(type)Returns global lists of entities in the current dimension of a specified type. Currently the following selectors are available:
- **: alllivingitemsplayers!playersentity_area(type, cx, cy, cz, dx, dy, dz)Returns entities of a specified type in an area centered on cx, cy, cz and
- * at most dx, dy, dz blocks away from the center point. Uses same selectors as entities_list
entity_selector(selector)Returns entities satisfying given vanilla entity selector. Most complex among all the methods of selecting - * entities, but the most capable. Selectors are cached so should be as fast as other methods of selecting entities.
- * - *spawn(name, pos, nbt?)Spawns and places an entity in world, like /summon vanilla command.
- * Requires a position to spawn, and optional extra nbt data to merge with the entity. What makes it different from calling
- * run('summon ...'), is the fact that you get the entity back as a return value, which is swell.
Unlike with blocks, that use plethora of vastly different querying functions, entities are queried with
- * query function and altered via modify function. Type of information needed or
- * values to be modified are different for each call
Using ~ (in) operator is an alias for query. Especially useful if a statement has
- * no arguments, which in this case can be radically simplified
- * query(p, 'name') <=> p ~ 'name' // much shorter and cleaner
- * query(p, 'holds', 'offhand') <=> p ~ l('holds', 'offhand') // not really but can be done
- *
- * query(e,'removed')Boolean. True if the entity is removed
- *query(e,'id')Returns numerical id of the entity. Most efficient way to keep track of entites in a script. Ids are only unique - * within current game session (ids are not preserved between restarts), and dimension (each dimension has its own ids - * which can overlap.
- *query(e,'uuid')Returns UUID (unique id) of the entity. Can be used to access entities with the other vanilla commands and remains unique - * regardless of the dimension, and is preserved between game restarts. - * Apparently players cannot be accessed via UUID, but name instead.
- *
- * map(entities_area('*',x,y,z,30,30,30),run('kill '+query(_,'id'))) // doesn't kill the player
- *
- * query(e,'pos')Triple of entity position
- *query(e,'location')Quin-tuple of entity position (x, y, and z coords), and rotation (yaw, pitch)
- *query(e,'x'), query(e,'y'), query(e,'z')Respective entity coordinate
- *query(e,'pitch'), query(e,'yaw')Pitch and Yaw or where entity is looking.
- *query(e,'look')Returns a 3d vector where the entity is looking.
- *query(e,'motion')Triple of entity motion vector, l(motion_x, motion_y, motion_z)
query(e,'motion_x'), query(e,'motion_y'), query(e,'motion_z')Respective component of the motion vector
- *query(e,'name'), query(e,'custom_name'), query(e,'type')String of entity name
- *- * query(e,'name') => Leatherworker - * query(e,'custom_name') => null - * query(e,'type') => villager - *- *
query(e,'is_riding')Boolean. True if riding another entity.
- *query(e,'is_ridden')Boolean. True if another entity is riding it.
- *query(e,'passengers')List of entities riding the entity.
- *query(e,'mount')Entity that e rides.
query(e,'tags')List of entity tags.
- *query(e,'has_tags',tag)Boolean, True if the entity is marked with tag.
query(e,'is_burning')Boolean, True if the entity is burning.
- *query(e,'fire')Number of remaining ticks of being on fire.
- *query(e,'silent')Boolean, True if the entity is silent.
- *query(e,'gravity')Boolean, True if the entity is affected by gravity, like most entities do.
- *query(e,'immune_to_fire')Boolean, True if the entity is immune to fire.
- *query(e,'dimension')Name of the dimension entity is in.
- *query(e,'height')Height of the entity.
- *query(e,'width')Width of the entity.
- *query(e,'eye_height')Eye height of the entity.
- *query(e,'age')Age, in ticks, of the entity, i.e. how long it existed.
- *query(e,'breeding_age')Breeding age of passive entity, in ticks. If negative it it time to adulthood, if positive, breeding cooldown
- *query(e,'despawn_timer')For living entities - the number of ticks they fall outside of immediate player presence.
- *query(e,'item')The item triple (name, count, nbt) if its an item entity, null otherwise
query(e,'count')Number of items in a stack from item entity, null otherwise
query(e,'pickup_delay')Retrieves pickup delay timeout for an item entity, null otherwise
query(e,'is_baby')Boolean, true if its a baby.
- *query(e,'target')Returns mob's attack target or null if none or not applicable.
- *query(e,'home')Returns creature's home position or null if none or not applicable.
- *query(e,'sneaking')Boolean, true if entity is sneaking.
- *query(e,'sprinting')Boolean, true if entity is sprinting.
- *query(e,'swimming')Boolean, true if entity is swimming.
- *query(e,'jumping')Boolean, true if entity is jumping.
- *query(e,'gamemode')String with gamemode, or null if not a player.
query(e,'gamemode_id')Good'ol gamemode id, or null if not a player.
- *query(e,'player_type')Returns null if the argument is not a player, otherwise:
singleplayer: for singleplayer gamemultiplayer: for players on a dedicated serverlan_host: for singleplayer owner that opened the game to LANlan_player: for all other players that connected to a LAN hostfake: any carpet-spanwed fake playershadow: any carpet-shadowed real playerrealms: ?query(e,'permission_level')Player's permission level, or null if not applicable for this entity.
query(e,'effect',name?)Without extra arguments, it returns list of effect active on a living entity.
- * Each entry is a triple of short effect name, amplifier, and remaining duration.
- * With an argument, if the living entity has not that potion active, returns null, otherwise
- * return a tuple of amplifier and remaining duration
- * query(p,'effect') => [[haste, 0, 177], [speed, 0, 177]] - * query(p,'effect','haste') => [0, 177] - * query(p,'effect','resistance') => null - *- *
query(e,'health')Number indicating remaining entity health, or null if not applicable.
query(e,'holds',slot?)Returns triple of short name, stack count, and NBT of item held in slot.
- * Available options for slot are:
mainhandoffhandheadchestlegsfeetIf slot is not specified, it defaults to the main hand.
query(e,'selected_slot')Number indicating the selected slot of entity inventory. Currently only applicable to players.
- *query(e,'facing', order?)Returns where the entity is facing. optional order (number from 0 to 5, and negative), indicating - * primary directions where entity is looking at. From most prominent (order 0) to opposite (order 5, or -1)
- *query(e,'trace', reach?, options?...)Returns the result of ray tracing from entity perspective, indicating what it is looking at. Default reach is 4.5
- * blocks (5 for creative players), and by default it traces for blocks and entities, identical to player attack tracing action.
- * This can be customized with options, use 'blocks' to trace for blocks, 'liquids' to include liquid blocks
- * as possible results, and 'entities' to trace entities. Any combination of the above is possible. When tracing
- * entities and blocks, blocks will take over the priority even if transparent or non-colliding (aka fighting chickens
- * in tall grass).
Regardless of the options selected, the result could be null if nothing is in reach, entity, if look
- * targets an entity, and block value if block is in reach.
query(e,'nbt',path?)Returns full NBT of the entity. If path is specified, it fetches only that portion of the NBT,
- * that corresponds to the path. For specification of path attribute, consult
- * vanilla /data get entity command.
Note that calls to nbt are considerably more expensive comparing to other
- * calls in Minecraft API, and should only be used when there is no other option. Returned value is of type nbt,
- * which can be further manipulated with nbt type objects via get, put, has, delete, so try to use API calls
- * first for that.
Like with entity querying, entity modifications happen through one function. Most position and movements - * modifications don't work currently on players as their position is controlled by clients.
- *Currently there is no ability to modify NBT directly, but you could always use run('data modify entity
modify(e,'remove')Removes (not kills) entity from the game.
- *modify(e,'kill')Kills the entity.
- *modify(e, 'pos', x, y, z), modify(e, 'pos', l(x,y,z) )Moves the entity to a specified coords.
- *modify(e, 'location', x, y, z, yaw, pitch), modify(e, 'location', l(x, y, z, yaw, pitch) )Changes full location vector all at once.
- *modify(e, 'x', x), modify(e, 'y', y), modify(e, 'z', z)Moves the entity in.... one direction.
- *modify(e, 'pitch', pitch), modify(e, 'yaw', yaw)Changes entity's pitch or yaw.
- *modify(e, 'move', x, y, z), modify(e, 'move', l(x,y,z) )Moves the entity by a vector from its current location.
- *modify(e, 'motion', x, y, z), modify(e, 'motion', l(x,y,z) )Sets the motion vector (where and how much entity is moving).
- *modify(e, 'motion_z', x), modify(e, 'motion_y', y), modify(e, 'motion_z', z)Sets the corresponding component of the motion vector.
- *modify(e, 'accelerate', x, y, z), modify(e, 'accelerate', l(x, y, z) )Adds a vector to the motion vector. Most realistic way to apply a force to an entity.
- *modify(e, 'custom_name'), modify(e, 'custom_name', name )modify(e, 'age', number)Modifies entity's internal age counter. Fiddling with this will affect directly - * behaviours of complex entities, so use it with caution.
- *modify(e, 'pickup_delay', number)modify(e, 'breeding_age', number)modify(e, 'despawn_timer', number)Sets a custom despawn timer value.
- *modify(e, 'dismount')Dismounts riding entity.
- *modify(e, 'mount', other)Mounts the entity to the other.
modify(e, 'drop_passengers')Shakes off all passengers.
- *modify(e, 'mount_passengers', passenger, ? ...), modify(e, 'mount_passengers', l(passengers) )Mounts on all listed entities on e.
modify(e, 'tag', tag, ? ...), modify(e, 'tag', l(tags) )Adds tag / tags to the entity.
- *modify(e, 'clear_tag', tag, ? ...), modify(e, 'clear_tag', l(tags) )Removes tag from entity.
- *modify(e, 'talk')Make noises.
- *modify(e, 'ai', boolean)If called with false value, it will disable AI in the mob. true will enable it again.
modify(e, 'no_clip', boolean)Sets if the entity obeys any collisions, including collisions with the terrain and basic physics. - * Not affecting players, since they are controlled client side
- *modify(e, 'effect', name, duration?, amplifier?, show_particles?, show_icon?)Applies status effect to the living entity. Takes several optional parameters, which default to 0,
- * true and true. If no duration is specified, or it is null or 0, the effect is removed.
modify(e, 'home', null), modify(e, 'home', block, distance?), modify(e, 'home', x, y, z, distance?)Sets AI to stay around the home position, within distance blocks from it. distance
- * defaults to 16 blocks. null removes it. May not work fully with mobs that have this AI built in, like
- * Villagers.
There is a number of events that happen to entities that you can attach your own code to in the form of event
- * handlers. The event handler is any function that runs in your package that accepts certain expected parameters, which
- * you can expand with your own arguments. When it comes to the moment when the given command needs to be executed, it
- * does so providing that number of arguments it accepts is equal number of event arguments, and extra arguments passed when
- * defining the callback with entity_event
The following events can be handled by entities.
- *'on_tick': executes every tick right before entity is ticked in the game. Required arguments: entity'on_death': executes once when a living entity dies. Required arguments: entity, reason'on_removed': execute once when an entity is removed. Required arguments: entity'on_damaged': executed every time a living entity is about to receive damage. Required arguments: entity, amount, source, attacking_entityIt doesn't mean that all entity types will have a chance to - * execute a given event, but entities will not error when you will attach inapplicable event to it.
- *entity_event(e, event, call_name, args...)Attaches specific function from the current package to be called upon the event, with extra args
- * curried to the original required arguments for the event handler
- * protect_villager(entity, amount, source, source_entity, healing_player) ->
- * (
- * if(source_entity && source_entity~'type' != 'player',
- * modify(entity, 'health', amount + entity~'health' );
- * particle('end_rod', pos(entity)+l(0,3,0));
- * print(str('%s healed thanks to %s', entity, healing_player))
- * )
- * );
- *
- * __on_player_interacts_with_entity(player, entity, hand) ->
- * (
- * if (entity~'type' == 'villager',
- * entity_event(entity, 'on_damage', 'protect_villager', player~'name')
- * )
- * )
- *
- * In this case this will protect a villager from entity damage (zombies, etc.) except players by granting all the health - * back to the villager after being harmed.
- *These functions help scan larger areas of blocks without using generic loop functions,
- * like nested loop.
scan(cx, cy, cz, dx, dy, dz, px?, py?, pz?, expr)Evaluates expression over area of blocks defined by its center (cx, cy, cz),
- * expanded in all directions by dx, dy, dz blocks, or optionally in negative with d coords,
- * and p coords in positive values. expr receives _x, _y, _z
- * as coords of current analyzed block and _ which represents the block itself.
volume(x1, y1, z1, x2, y2, z2, expr)Evaluates expression for each block in the area, the same as the scanfunction, but using two opposite
- * corners of the rectangular cuboid. Any corners can be specified, its like you would do with /fill command
neighbours(x, y, z), neighbours(block), neighbours(l(x,y,z))Returns the list of 6 neighbouring blocks to the argument. Commonly used with other loop functions like for
- * for(neighbours(x,y,z),air(_)) => 4 // number of air blocks around a block - *- *
rect(cx, cy, cz, dx?, dy?, dz?, px?, py?, pz?)returns an iterator, just like range function that iterates over rectangular cubarea of blocks. If
- * only center point is specified, it iterates over 27 blocks. If d arguments are specified, expands selection
- * of respective number of blocks in each direction. If p arguments are specified, it uses d for
- * negative offset, and p for positive.
diamond(cx, cy, cz, radius?, height?)Iterates over a diamond like area of blocks. With no radius and height, its 7 blocks centered around the middle - * (block + neighbours). With a radius specified, it expands shape on x and z coords, and with a custom height, on y. Any of these can be - * zero as well. radius of 0 makes a stick, height of 0 makes a diamond shape pad.
- *Collection of other methods that control smaller, yet still important aspects of the game
- *sound(name, pos, volume?, pitch?)Plays a specific sound name, at block or position pos, with optional
- * volume and modified pitch. pos can be either a block, triple of coords,
- * or a list of thee numbers. Uses the same options as a corresponding playsound command.
particle(name, pos, count?. spread?, speed?, playername?)Renders a cloud of particles name centered around pos position, by default
- * count 10 of them, default speed of 0, and to all players nearby, but these
- * options can be changed via optional arguments. Follow vanilla /particle command on details on those
- * options. Valid particle names are for example
- * 'angry_villager', 'item diamond', 'block stone', 'dust 0.8 0.1 0.1 4'
particle_line(name, pos, pos2, density?)Renders a line of particles from point pos to pos2 with supplied density (defaults 1),
- * which indicates how far part you would want particles to appear, so 0.1 means one every 10cm.
particle_rect(name, pos, pos2, density?)Renders a cuboid of particles between point pos to pos2 with supplied density.
create_marker(text, pos, rotation?, block?)Spawns a (permanent) marker entity with text or block at position. Returns that entity for further manipulations. - * Unloading the app that spawned them will cause all the markers from the loaded portion of the world to be removed. - * Also - if the game loads that marker in the future and the app is not loaded, it will be removed as well.
- *remove_all_markers()Removes all scarpet markers from the loaded portion of the world created by this app, in case you didn't want - * to do the proper cleanup
- *nbt(expr)Treats the argument as a nbt serializable string and returns its nbt value.
- * In case nbt is not in a correct nbt compound tag format, it will return null value.
Consult section about container operations in Expression to learn about possible operations on nbt values.
escape_nbt(expr)Excapes all the special characters in the string or nbt tag and returns a string that can be stored in nbt directly as - * a string value.
- *print(expr)Displays the result of the expression to the chat. Overrides default scarpet behaviour of
- * sending everyting to stderr.
logger(expr)Prints the message to system logs, and not to chat.
- *run(expr)Runs a vanilla command from the string result of the expr and returns its success count
- * run('fill 1 1 1 10 10 10 air') -> 123 // 123 block were filled, this operation was successful 123 times out of a possible 1000 blocks volume
- * run('give @s stone 4') -> 1 // this operation was successful once
- *
- * save()Performs autosave, saves all chunks, player data, etc. Useful for programs where autosave is disabled - * due to performance reasons and saves the world only on demand.
- *load_app_data(), load_app_data(file)Loads the app data associated with the app from the world /scripts folder. Without argument returns the memory - * managed and buffered / throttled NBT tag. With a file name - reads explicitly a file with that name from the scripts - * folder.
- *You can use app data to save non-vanilla information separately from the world and other scripts.
- *store_app_data(tag), store_app_data(tag, file)Stores the app data associated with the app from the world /scripts folder. With the file parameter
- * saves immediately and with every call, without file parameter, it may take up to 10 seconds for the output
- * file to sync preventing flickering in case this tag changes frequently. It will be synced when server closes.
tick_time()Returns game tick counter. Can be used to run certain operations every n-th ticks, or to count in-game time
- *game_tick(mstime?)Causes game to run for one tick. By default runs it and returns control to the program, but can optionally
- * accept expected tick length, in milliseconds. You can't use it to permanently change the game speed, but
- * setting longer commands with custom tick speeds can be interrupted via /script stop command
- * loop(1000,game_tick()) // runs the game as fast as it can for 1000 ticks - * loop(1000,game_tick(100)) // runs the game twice as slow for 1000 ticks - *- *
seed()Returns current world seed.
- *current_dimension()Returns current dimension that the script runs in.
- *in_dimension(smth, expr)Evaluates the expression expr with different dimension execution context. smth can
- * be an entity, world-localized block, so not block('stone'), or a string representing a dimension like:
- * 'nether', 'the_nether', 'end' or 'overworld', etc.
schedule(delay, function, args...)Schedules a user defined function to run with a specified delay ticks of delay.
- * Scheduled functions run at the end of the tick, and they will run in order they were scheduled.
statistic(player, category, entry)Queries in-game statistics for certain values. Categories include:
- *mined: blocks minedcrafted: items craftedused: items usedbroken: items brokenpicked_up: items picked updropped: items droppedkilled: mobs killedkilled_by: blocks minedcustom: various random statsFor the options of entry, consult your statistics page, or give it a guess.
The call will return null if the statistics options are incorrect, or player didn't get these
- * in their history. If the player encountered the statistic, or game created for him empty one, it will
- * return a number. Scarpet will not affect the entries of the statistics, even if it is just creating empty ones.
- * With null response it could either mean your input is wrong, or statistic has effectively
- * a value of 0.
plop(pos, what)Plops a structure or a feature at a given pos, so block, triple position coordinates
- * or a list of coordinates. To what gets plopped and exactly where it often depends on the
- * feature or structure itself. For example, all structures are chunk aligned, and often span multiple chunks.
- * Repeated calls to plop a structure in the same chunk would result either in the same structure generated on
- * top of each other, or with different state, but same position. Most
- * structures generate at specific altitudes, which are hardcoded, or with certain blocks around them. API will cancel
- * all extra position / biome / random requirements for structure / feature placement, but some hardcoded limitations
- * may still cause some of structures/features not to place. Some features require special blocks to be present, like
- * coral -> water or ice spikes -> snow block, and for some features, like fossils, placement is all sorts of
- * messed up. This can be partially avoided for structures by setting their structure information via set_structure
- * which sets it without looking into world blocks, and then use plop to fill it with blocks. This may, or may not work
- * All generated structures will retain their properties, like mob spawning, however in many cases the world / dimension - * itself has certain rules to spawn mobs, like plopping a nether fortress in the overworld will not spawn nether mobs - * because nether mobs can spawn only in the nether, but plopped in the nether - will behave like a valid nether - * fortress.
- *plop will not use world random number generator to generate structures and features, but its own.
- * This has a benefit that they will generate properly randomly, not the same time every time
Structure list:
- *monument: Ocean Monument. Generates at fixed Y coordinate, surrounds itself with water.fortress: Nether Fortress. Altitude varies, but its bounded by the code.mansion: Woodland Mansionjungle_temple: Jungle Templedesert_temple: Desert Temple. Generates at fixed Y altitude.end_city: End City with Shulkersigloo: Iglooshipwreck: Shipwreck, version1?shipwreck2: Shipwreck, version2?witch_hutocean_ruin, ocean_ruin_small, ocean_ruin_tall: Stone variants of ocean ruins.ocean_ruin_warm, ocean_ruin_warm_small, ocean_ruin_warm_tall: Sandstone variants of ocean ruins.treasure: A treasure chest. Yes, its a whole structure.pillager_outpost: A pillager outpost.mineshaft: A mineshaft.mineshaft_mesa: A Mesa (Badlands) version of a mineshaft.village: Plains, oak village.village_desert: Desert, sandstone village.village_savanna: Savanna, acacia village.village_taiga: Taiga, spruce village.village_snowy: Resolute, Canada.Feature list:
- *oakoak_beehive: oak with a hive (1.15+).oak_large: oak with branches.oak_large_beehive: oak with branches and a beehive (1.15+).birchbirch_large: tall variant of birch tree.shrub: low bushes that grow in jungles.shrub_acacia: low bush but configured with acacia (1.14 only)shrub_snowy: low bush with white blocks (1.14 only)jungle: a treejungle_large: 2x2 jungle treesprucespruce_large: 2x2 spruce treepine: spruce with minimal leafage (1.15+)pine_large: 2x2 spruce with minimal leafage (1.15+)spruce_matchstick: see 1.15 pine (1.14 only).spruce_matchstick_large: see 1.15 pine_large (1.14 only).dark_oakacaciaoak_swamp: oak with more leaves and vines.well: desert wellgrass: a few spots of tall grassgrass_jungle: little bushier grass feature (1.14 only)lush_grass: grass with patchy ferns (1.15+)tall_grass: 2-high grass patch (1.15+)fern: a few random 2-high fernscactus: random cactidead_bush: a few random dead bushifossils: underground fossils, placement little wonkymushroom_brown: large brown mushroom.mushroom_red: large red mushroom.ice_spike: ice spike. Require snow block below to place.glowstone: glowstone cluster. Required netherrack above it.melon: a patch of melonsmelon_pile: a pile of melons (1.15+)pumpkin: a patch of pumpkinspumpkin_pile: a pile of pumpkins (1.15+)sugarcanelilypaddungeon: Dungeon. These are hard to place, and fail often.iceberg: Iceberg. Generate at sea level.iceberg_blue: Blue ice iceberg.lakelava_lakeend_islandchorus: Chorus plant. Require endstone to place.sea_grass: a patch of sea grass. Require water.sea_grass_river: a variant.kelpcoral_tree, coral_mushroom, coral_claw: various coral types, random color.coral: random coral structure. Require water to spawn.sea_pickleboulder: A rocky, mossy formation from a giant taiga biome. Doesn't update client properly,
- * needs relogging./script scan, /script fill and /script outline commandsThese commands can be used to evaluate an expression over an area of blocks. They all need to have specified
- * the origin of the analyzed area (which is used as referenced (0,0,0), and two corners of an area to analyzed. If
- * you would want that the script block coordinates refer to the actual world coordinates, use origin of 0 0 0,
- * or if it doesn't matter, duplicating coordinates of one of the corners is the easiest way.
These commands, unlike raw /script run are limited by vanilla fill / clone command
- * limit of 32k blocks, which can be altered with carpet mod's own /carpet fillLimit command.
/script scan origin<x y z> corner<x y z> corner<x y z> exprEvaluates expression for each point in the area and returns number of successes (result was positive). Since - * the command by itself doesn't affect the area, the effects would be in side effects.
- */script fill origin<x y z> corner<x y z> corner<x y z> "expr" <block> (? replace <replacement>) Think of it as a regular fill command, that sets blocks based on whether a result of the command was successful.
- * Note that the expression is in quotes. Thankfully string constants in scarpet use single quotes. Can be used
- * to fill complex geometric shapes.
/script outline origin<x y z> corner<x y z> corner<x y z> "expr" <block> (? replace <replacement>) Similar to fill command it evaluates an expression for each block in the area, but in this case setting blocks
- * where condition was true and any of the neighbouring blocks were evaluated negatively. This allows to create surface areas,
- * like sphere for example, without resorting to various rounding modes and tricks.
Here is an example of seven ways to draw a sphere of radius of 32 blocks around 0 100 0:
- *- * /script outline 0 100 0 -40 60 -40 40 140 40 "x*x+y*y+z*z < 32*32" white_stained_glass replace air - * /script outline 0 100 0 -40 60 -40 40 140 40 "x*x+y*y+z*z <= 32*32" white_stained_glass replace air - * /script outline 0 100 0 -40 60 -40 40 140 40 "x*x+y*y+z*z < 32.5*32.5" white_stained_glass replace air - * /script fill 0 100 0 -40 60 -40 40 140 40 "floor(sqrt(x*x+y*y+z*z)) == 32" white_stained_glass replace air - * /script fill 0 100 0 -40 60 -40 40 140 40 "round(sqrt(x*x+y*y+z*z)) == 32" white_stained_glass replace air - * /script fill 0 100 0 -40 60 -40 40 140 40 "ceil(sqrt(x*x+y*y+z*z)) == 32" white_stained_glass replace air - * /draw sphere 0 100 0 32 white_stained_glass replace air - * - * fluffy ball round(sqrt(x*x+y*y+z*z)-rand(abs(y)))==32 - * - *- *
The last method is the one that world edit is using (part of carpet mod). It turns out that the outline method with 32.5 radius,
- * fill method with round function and draw command are equivalent
/script run commandPrimary way to input commands. The command executes in the context, position, and dimension of the executing
- * player, commandblock, etc... The command receives 4 variables, x, y, z
- * and p indicating position and the executing entity of the command.
- * You will receive tab completion suggestions as you type your code suggesting functions and global variables.
- * It is advisable to use /execute in ... at ... as ... run script run ... or similar, to simulate running
- * commands in a different scope
/script invoke / invokepoint / invokearea, /script globals commandsinvoke family of commands provide convenient way to invoke stored procedures (i.e. functions
- * that has been defined previously by any running script. To view current stored procedure set,
- * run /script globals(or /script globals all to display all functions even hidden ones),
- * to define a new stored procedure, just run a /script run function(a,b) -> ( ... )
- * command with your procedure once, and to forget a procedure, use undef function:
- * /script run undef('function')
/script invoke <fun> <args?> ... Equivalent of running /script run fun(args, ...), but you get the benefit of getting the tab completion of the
- * command name, and lower permission level required to run these (since player is not capable of running any custom code
- * in this case, only this that has been executed before by an operator). Arguments will be checked for validity, and
- * you can only pass simple values as arguments (strings, numbers, or null value). Use quotes to include
- * whitespaces in argument strings.
Command will check provided arguments with required arguments (count) and fail if not enough or too much arguments - * are provided. Operators defining functions are advised to use descriptive arguments names, as these will be visible - * for invokers and form the base of understanding what each argument does.
- *invoke family of commands will tab complete any stored function that does not start with '_',
- * it will still allow to run procedures starting with '_' but not suggest them, and ban execution of any
- * hidden stored procedures, so ones that start with '__'. In case operator needs to use subroutines
- * for convenience and don't want to expose them to the invoke callers, they can use this mechanic.
- * /script run example_function(const, phrase, price) -> print(const+' '+phrase+' '+price) - * /script invoke example_function pi costs 5 - *- *
/script invokepoint <fun> <coords x y z> <args?> ... It is equivalent to invoke except it assumes that the first three arguments are coordinates, and provides
- * coordinates tab completion, with looking at... mechanics for convenience. All other arguments are expected
- * at the end
/script invokearea <fun> <coords x y z> <coords x y z> <args?> ... It is equivalent to invoke except it assumes that the first three arguments are one set of ccordinates,
- * followed by the second set of coordinates, providing tab completion, with looking at... mechanics for convenience,
- * followed by any other required arguments
/script load / unload <app> (global?), /script in <app> commandsload / unload commands allow for very conventient way of writing your code, providing it to the game
- * and distribute with your worlds without the need of use of commandblocks. Just place your scarpet code in the /scripts
- * folder of your world files and make sure it ends with .sc extension. The good thing about editing that
- * code is that you can no only use normal editing without the need of marking of newlines, but you can also use
- * comments in your code.
a comment is anything that starts with a double slash, and continues to the end of the line:
- *- * foo = 1; - * //This is a comment - * bar = 2; - * // This never worked, so I commented it out - * // baz = foo() - *- * - *
/script load/unload <app> (?global) Loading operation will load that script code from disk and execute it right away. You would probably use it to
- * load some stored procedures to be used for later. To reload the module, just type /script load again.
- * Reloading removes all the current global state (globals and functions) that were added later by the module.
Loading a module, if it contains a __command() method, will attempt to registed a command with that
- * app name, and register all public (no underscore) functions available in the module as subcommands. It will also
- * bind specific events to the event system (check Events section for details).
Loaded apps have the ability to store and load external files, especially their persistent tag state.
- * For that check load_app_data and store_app_data functions.
If an app defines __config method, and that method returns a map, it will be used to apply custom
- * settings for this app. Currently the following options are supported:
scope: default scope for global variables for the app, Default is 'player' which means
- * that globals and defined functions will be unique for each player so that apps for each player will run in
- * isolation. This is useful in tool-like applications. Another option is 'global' which shares global state for all
- * runs on the server - applicable to 'block' like solutions, where custom behaviours are applied to blocks.stay_loaded: defaults to false. If true, and /carpet scriptsAutoload is turned on,
- * the following apps will stay loaded after startup. Otherwise, after reading a code, and fetching the config, server
- * will drop them down. This is to allow to store multiple apps on the server/world and selectively decide which one
- * should be running at startup. WARNING: all apps will run once at startup anyways, so be aware that their actions
- * that are called statically, will be performed once anyways.Unloading an app removes all of its state from the game, disables commands, and removes bounded events,
- * and saves its global state. If more
- * cleanup is needed, one can define an __on_close() function which will be executed when the module is unloaded,
- * or server is closing, or crashing. However, there is no need to do that explicitly for the things mentioned
- * in the previous statement.
Scripts can be loaded in shared(global) and player mode. Default is player, so all globals and stored functions are
- * individual for each player, meaning scripts don't need to worry about making sure they store some intermittent data
- * for each player independently. In global mode - all global values and stored functions are shared among all players.
- * To access specific player data with commandblocks, use /execute as (player) run script in (app) run ...
- * To access global/server state, you need to disown the command from any player, so use a commandblock, or any arbitrary
- * entity: /execute as @e[type=bat,limit=1] run script in (module) globals for instance.
- *
/script in <app> ... Allows to run normal /script commands in a specific app, like run, invoke,..., globals etc...
Provides the ability to execute specific function whenever an event occurs. The functions to be registered
- * need to conform with the arguments to the event specification. When loading module functions, each function that
- * starts with __on_... and has the required arguments, will be bound automatically.
- * In case of player specific modules, all player action events will be directed to the appropriate player space, and
- * all tick events will be executed in the global context, so its not a good idea to mix these two, so use either of these,
- * or use commands to call tick events directly, or handle player specific data inside a module. In near future using
- * global events (on_tick, on_chunk_generated) will be not allowed in player scoped apps.
Here is a list of events that can be handled by scarpet. This list includes prefixes required by modules to - * autoload them, but you can add any function to any event if it accepts required number of parameters:
- *- * __on_tick() // can access blocks and entities in the overworld - * __on_tick_nether() // can access blocks and entities in the nether - * __on_tick_ender() // can access blocks and entities in the end - * __on_chunk_generated(x,z) // called after a chunk is promoted to the full chunk, - * // prodiving lowest x and z coords in the chunk - * // event will not work with optifine installed in the game - * // player specific callbacks - * __on_player_uses_item(player, item_tuple, hand) // right click action - * __on_player_releases_item(player, item_tuple, hand) // client action (e.g. bow) - * __on_player_finishes_using_item(player, item_tuple, hand)) // server action (e.g. food), called item is from before it is used. - * __on_player_clicks_block(player, block, face) // left click attack on a block - * __on_player_breaks_block(player, block) // called after block is broken (the caller receives previous blockstate) - * __on_player_right_clicks_block(player, item_tuple, hand, block, face, hitvec) // player right clicks block with anything - * __on_player_interacts_with_block(player, hand, block, face, hitvec) //right click on a block resulted in activation of said block - * __on_player_places_block(player, item_tuple, hand, block) // player have just placed the block. - * __on_player_interacts_with_entity(player, entity, hand) - * __on_player_attacks_entity(player, entity) - * __on_player_rides(player, forward, strafe, jumping, sneaking) - * __on_player_jumps(player) - * __on_player_deploys_elytra(player) - * __on_player_wakes_up(player) - * __on_player_starts_sneaking(player) - * __on_player_stops_sneaking(player) - * __on_player_starts_sprinting(player) - * __on_player_stops_sprinting(player) - * __on_player_drops_item(player) - * __on_player_drops_stack(player) - * - * __on_statistic(player, category, event, value) // player statistic changes - *- *
/script event commandused to display current events and bounded functions. use add_to ro register new event, or remove_from
- * to unbind a specific function from an event. Function to be bounded to an event needs to have the same
- * number of parameters as the action is attempting to bind to (see list above). All calls in modules
- * loaded via /script load that have functions listed above will be automatically bounded and unbounded when
- * script is unloaded.
scarpet programming language (towards version 1.7).Scarpet (a.k.a. Carpet Script, or Script for Carpet) is a programming language designed to provide - * the ability to write custom programs to run within Minecraft and - * interact with the world.
- * - *The project was initially built based on the EvalEx project, - * however it now diverged so far away from the original implementation, - * it would be hard to tell it without this mention. - * EvalEx is a handy expression evaluator for Java, that - * allows to evaluate simple mathematical and boolean expressions. - * For more information, see: - * EvalEx GitHub - * repository
- * - *This specification is divided into two sections: this one is agnostic - * to any Minecraft related features and could function on its own, and CarpetExpression for - * Minecraft specific routines and world manipulation functions.
- * - *
- * script run print('Hello World!')
- *
- * or an OVERLY complex example:
- *
- * /script run
- * block_check(x1, y1, z1, x2, y2, z2, block_to_check) ->
- * (
- * l(minx, maxx) = sort(l(x1, x2));
- * l(miny, maxy) = sort(l(y1, y2));
- * l(minz, maxz) = sort(l(z1, z2));
- * 'Need to compute the size of the area of course';
- * 'Cause this language doesn\'t support comments in the command mode';
- * xsize = maxx - minx + 1;
- * ysize = maxy - miny + 1;
- * zsize = maxz - minz + 1;
- * total_count = 0;
- * loop(xsize,
- * xx = minx + _ ;
- * loop(ysize,
- * yy = miny + _ ;
- * loop(zsize,
- * zz = minz + _ ;
- * if ( block(xx,yy,zz) == block_to_check,
- * total_count += ceil(rand(1))
- * )
- * )
- * )
- * );
- * total_count
- * );
- * check_area_around_closest_player_for_block(block_to_check) ->
- * (
- * closest_player = player();
- * l(posx, posy, posz) = query(closest_player, 'pos');
- * total_count = block_check( posx-8,1,posz-8, posx+8,17,posz+8, block_to_check);
- * print('There is '+total_count+' of '+block_to_check+' around you')
- * )
- *
- * /script invoke check_area_around_closest_player_for_block 'diamond_ore'
- *
- *
- * or simply
- *
- * script run print('There is'+for(rect(x,9,z,8,8,8), _ == 'diamond_ore')+' diamond ore around you')
- *
- * It definitely pays to check what higher level scarpet functions have to offer.
- * You can think of an program like a mathematical expression, like
- * "2.4*sin(45)/(2-4)" or "sin(y)>0 & max(z, 3)>3"
- * Writing a program, is like writing a 2+3, just a bit longer
Programs consist of constants, like 2, 3.14, pi, or 'foo',
- * operators like +, /, ->, variables which you can define, like foo
- * or special ones that will be defined for you, like _x, or _ , which I specific to
- * a each built in function, and functions with name, and arguments in the form of f(a,b,c), where
- * f is the function name, and a, b, c are the arguments which can be any other expression.
- * And that's all the parts of the language, so all in all - sounds quite simple.
- * Like any other proper programming language, scarpet needs brackets, basically to identify
- * where stuff begins and where it ends. In the languages that uses much more complicated constructs, like Java,
- * they tend to use all sort of them, round ones to indicate function calls, curly to indicate section of code,
- * square to access lists, pointy for generic types etc... I mean - there is no etc, cause they have exhausted
- * all the bracket options...
- *
Scarpet is different, since it runs everything based on functions (although its not per se a functional language like lisp)
- * only needs the round brackets for everything, and it is up to the programmer to organize its code so its readable,
- * as adding more brackets does not have any effect on the performance of the programs as they are compiled before they are executed.
- * Look at the following example usage of if() function:
- *
- * if(x<y+6,set(x,8+y,z,'air');plop(x,top('surface',x,z),z,'birch'),sin(query(player(),'yaw'))>0.5,plop(0,0,0,'boulder'),particle('fire',x,y,z))
- *
- * Would you prefer to read
- *
- * if( x<y+6,
- * set(x,8+y,z,'air');
- * plop(x,top('surface',x,z),z,'birch'),
- * sin(query(player(),'yaw'))>0.5,
- * plop(0,0,0,'boulder'),
- * particle('fire',x,y,z)
- * )
- *
- * Or rather:
- *
- * if
- * (
- * x<y+6,
- * (
- * set(x,8+y,z,'air');
- * plop(x,top('surface',x,z),z,'birch')
- * ),
- *
- * sin(query(player(),'yaw'))>0.5,
- * (
- * plop(0,0,0,'boulder')
- * ),
- *
- * particle('fire',x,y,z)
- * )
- *
- * Whichever style you prefer it doesn't matter. It typically depends on the situation and the complexity of the - * subcomponents. No matter how many whitespaces and extra brackets you add - the code will evaluate to exactly the - * same expression, and will run exactly the same, so make sure your programs are nice and clean so others don't - * have problems with them
- * - *
- * Users can define functions in the form fun(args....) -> expression and they are compiled and saved
- * for further execution in this but also subsequent calls of /script command. Functions can also be assigned to variables,
- * passed as arguments, called with call function, but in most cases you would want to call them directly
- * by name, in the form of fun(args...).
- * This means that once defined functions
- * are saved with the world for further use. For variables, there are two types of them,
- * global - which are shared anywhere in the code, and those are all which name starts with 'global_', and
- * local variables which is everything else and those are only visible inside each function.
- * This also means that all the parameters in functions are passed 'by value', not 'by reference'.
- *
Functions can still 'borrow' variables from the outer scope,
- * by adding them to the function signature wrapped around built-in function outer.
- * It adds the specified value to the function call stack so they behave exactly like capturing lambdas in Java, but
- * unlike java captured variables don't need to be final. Scarpet will just attach their new values at the time of the
- * function definition, even if they change later. Most value will be copied, but mutable values, like maps or lists, allow
- * to keep the 'state' with the function, allowing them to have memory and act like objects so to speak.
- * . Check outer(var) for details.
Note that this should only apply to pasting your code to execute with commandblock. Scarpet recommends placing your
- * code in apps (files with .sc extension that can be placed inside "/scripts" folder in the world files
- * and loaded as a scarpet app with command /script load [app_name]. Scarpet apps loaded from disk should only
- * contain code, no need to start with "/script run" prefix
The following is the code that could be provided in a foo.sc app file located in world /scripts folder
- * run_program() -> (
- * loop( 10,
- * // looping 10 times
- * // comments are allowed in scripts located in world files
- * // since we can tell where that line ends
- * foo = floor(rand(10));
- * check_not_zero(foo);
- * print(_+' - foo: '+foo);
- * print(' reciprocal: '+ _/foo )
- * )
- * );
- * check_not_zero(foo) -> (
- * if (foo==0, foo = 1)
- * )
- *
- * Which we then call in-game with:
- *- * /script load foo - * /script in foo invoke run_program - *- *
However the following code can also be input as a command, or in a command block.
- * - *Since the maximum command that can be input to the chat is limited in length, you will be probably inserting your
- * programs by pasting them to command blocks or reading from world files, however pasting to command blocks will remove some whitespaces and squish
- * your newlines making the code not readable. If you are pasting a program that is perfect and will never cause an error,
- * I salute you, but for the most part it is quite likely that your program might break, either at compile time, when
- * its initially analyzed, or at execute time, when you suddenly attempt to divide something by zero. In these cases
- * you would want to get a meaningful error message, but for that you would need to indicate for the compiler where
- * did you put these new lines, since command block would squish them. For that, place at the beginning
- * of the line to let the compiler know where are you. This makes so that $ is the only character that is
- * illegal in programs, since it will be replaced with new lines. As far as I know, $ is not used
- * anywhere inside Minecraft identifiers, so this shouldn't hinder the abilities of your programs.
Consider the following program executed as command block command:
- *
- * /script run
- * run_program() -> (
- * loop( 10,
- * foo = floor(rand(_));
- * check_not_zero(foo);
- * print(_+' - foo: '+foo);
- * print(' reciprocal: '+ _/foo )
- * )
- * );
- * check_not_zero(foo) -> (
- * if (foo==0, foo = 1)
- * )
- *
- *
- * Lets say that the intention was to check if the bar is zero and prevent division by zero in print,
- * but because the foo is passed as a variable, it never changes the original foo value.
- * Because of the inevitable division by zero, we get the following message:
- *
- * Your math is wrong, Incorrect number format for NaN at pos 98
- * run_program() -> ( loop( 10, foo = floor(rand(_)); check_not_zero(foo); print(_+' - foo: '+foo);
- * HERE>> print(' reciprocal: '+ _/foo ) ));check_not_zero(foo) -> ( if (foo==0, foo = 1))
- *
- *
- * As we can see, we got our problem where the result of the mathematical operation was not a number (infinity, so not a number),
- * however by pasting our program
- * into the command made it squish the newlines so while it is clear where the error happened and we still can track the error down,
- * the position of the error (98) is not very helpful and wouldn't be useful if the program gets significantly longer.
- * To combat this issue we can precede every line of the script with dollar signs $:
- *
- * /script run
- * $run_program() -> (
- * $ loop( 10,
- * $ foo = floor(rand(_));
- * $ check_not_zero(foo);
- * $ print(_+' - foo: '+foo);
- * $ print(' reciprocal: '+ _/foo )
- * $ )
- * $);
- * $check_not_zero(foo) -> (
- * $ if (foo==0, foo = 1)
- * $)
- *
- *
- * Then we get the following error message
- * - *
- * Your math is wrong, Incorrect number format for NaN at line 7, pos 2
- * print(_+' - foo: '+foo);
- * HERE>> print(' reciprocal: '+ _/foo )
- * )
- *
- *
- *
- * As we can note not only we get much more concise snippet, but also information about the line - * number and position, so means its way easier to locate the potential problems problem
- * - *Obviously that's not the way we intended this program to work. To get it foo modified via
- * a function call, we would either return it as a result and assign it to the new variable:
- *
- * foo = check_not_zero(foo); - * ... - * check_not_zero(foo) -> if(foo == 0, 1, foo) - *- *
.. or convert it to a global variable, which in this case passing as an argument is not required
- *- * global_foo = floor(rand(10)); - * check_foo_not_zero(); - * ... - * check_foo_not_zero() -> if(global_foo == 0, global_foo = 1) - *- * - */ - public class Expression { private static final Map
scarpet provides a number of constants that can be used literally in scripts
null: nothing, zilch, not even falsetrue: pure true, or just 1 (one)false: false truth, or true falsth, 0 (zero) actuallypi: for the fans of perimeters, its a perimeter of an apple pi of diameter 1. About 3.14euler: clever guy. Derivative of its exponent is goto 1. About 2.72Apart from that, there is a bunch of system variables, that start with _ that are set by
- * scarpet built-ins, like _, typically each consecutive value in loops,
- * _i indicating iteration, or _a like an accumulator for reduce
- * function. Certain calls to Minecraft specific calls would also set _x,
- * _y, _z, indicating block positions. All variables starting with
- * _ are read-only, and cannot be declared and modified in client code.
scarpet accepts numeric and string liters constants.
- * Numbers look like 1, 2.5, -3e-7, 0xff, and are internally represented as Java's double
- * but scarpet will try to trim trailing zeros as much as possible so if you need to use them as intergers,
- * you can. Strings using single quoting, for multiple reasons, but primarily to allow for easier use of strings inside
- * doubly quoted command arguments (when passing a script as a parameter of /script fill for example,
- * or when typing in jsons inside scarpet to feed back into a /data merge command for example. Strings also
- * use backslashes \ for quoting special characters, in both plain strings and regular expressions
- * 'foo'
- * print('This doesn\'t work')
- * nbt ~ '\\.foo' // matching '.' as a '.', not 'any character match'
- *
- * Operator ;To effectively write programs that have more than one line, a programmer needs way to specify a sequence of
- * commands that execute one after another. In scarpet this can be achieved with ;. Its an operator,
- * and by separating statements with semicolons. And since whitespaces and $ signs are all treats as
- * whitespaces, how you layout your code doesn't matter, as long as it is readable to everyone involved.
- * expr; - * expr; - * expr; - * expr - *- *
Notice that the last expression is not followed by a semicolon. Since instruction separation is functional
- * in scarpet, and not barely an instruction delimiter, terminating the code with a dangling operator
- * wouldn't be valid. Having said that, since many programming languages don't care about the number of op terminators
- * programmers use, carpet preprocessor will remove all unnecessary semicolons from scripts when compiled.
In general expr; expr; expr; expr is equivalent to
- * (((expr ; expr) ; expr) ; expr).
Result of the evaluated expression is the same as the result of the second expression, but first expression is - * also evaluated for sideeffects
- *- * expr1 ; expr2 => expr2 // with expr1 as a sideeffect - *- *
All defined functions are compiled, stored persistently, and available globally -
- * accessible to all other scripts. Functions can only be undefined via call to undef('fun'), which
- * would erase global entry for function fun. Since all variables have local scope inside each function,
- * one way to share large objects is via global variables
- *
Any variable that is used with a name that starts with 'global_' will be stored and accessible globally,
- * not, inside current scope. It will also persist across scripts, so if a procedure needs to use its own construct, it needs to
- * define it, or initialize it explicitly, or undefine it via undef
- * a() -> global_list+=1; global_list = l(1,2,3); a(); a(); global_list // => [1,2,3,1,1] - *- *
Operator ->To organize code better than a flat sequence of operations, one can define functions. Definition is correct if - * has the following form
- *- * fun(args, ...) -> expr - *- *
Where fun(args, ...) is a function signature indicating function name, number of arguments,
- * and their names, and expr is an expression (can be complex) that is evaluated when fun is called.
- * Names in the signature don't need to be used anywhere else, other occurrences of these names
- * will be masked in this function scope.
- * Function call creates new scope for variables inside expr, so all non-global variables are not
- * visible from the caller scope. All parameters are passed by value to the new scope, including lists and other
- * containers, however their copy will be shallow.
The function returns its name as a string, which means it can be used to call it later with the call function
Using _ as the function name creates anonymous function, so each time _ function is defined,
- * it will be given a unique name, which you can pass somewhere else to get this function called.
- * a(lst) -> lst+=1; list = l(1,2,3); a(list); a(list); list // => [1,2,3] - *- *
In case the inner function wants to operate and modify larger objects, lists from the outer
- * scope, but not global, it needs to use outer function in function signature
outer(arg)outer function can only be used in the function signature, and it will
- * cause an error everywhere else. It saves the value of that variable from the outer scope and allows
- * its use in the inner scope. This is a similar behaviour to using outer variables in lambda function definitions
- * from Java, except here you have to specify which variables you want to use, and borrow
This mechanism can be used to use static mutable objects without the need of using global_... variables
- * list = l(1,2,3); a(outer(list)) -> list+=1; a(); a(); list // => [1,2,3,1,1] - *- *
The return value of a function is the value of the last expression. This as the same effect as using outer - * or global lists, but is more expensive
- *- * a(lst) -> lst+=1; list = l(1,2,3); list=a(list); list=a(list); list // => [1,2,3,1,1] - *- *
Ability to combine more statements into one expression, with functions, passing parameters, and global and outer - * scoping allow to organize even larger scripts
- *import(module_name, symbols ...)Imports symbols from other apps and libraries into the current one: global variables or functions, allowing - * to use them in the current app. This include - * other symbols imported by these modules. Scarpet supports cicular dependencies, but if symbols are used directly in - * the module body rather than functions, it may not be able to retrieve them. Returns full list of available symbols - * that could be imported from this module, which can be used to debug import issues, and list contents of libraries. - *
- *call(function, args.....)calls a user defined function with specified arguments. It is equivalent to calling function(args...)
- * directly except you can use it with function value, or name instead. This means you can pass functions to other user defined
- * functions as arguments and call them with call internally. And since function definitions return the
- * defined function, they can be defined in place as anonymous functions.
Little technical note: the use of _ in expression passed to built in functions is much more efficient due to
- * not creating new call stacks for each invoked function, but anonymous functions is the only mechanism available
- * for programmers with their own lambda arguments
- * my_map(list, function) -> map(list, call(function, _)); - * my_map(l(1,2,3), _(x) -> x*x); // => [1,4,9] - * - * profile_expr(my_map(l(1,2,3), _(x) -> x*x)); // => ~32000 - * sq(x) -> x*x; profile_expr(my_map(l(1,2,3), 'sq')); // => ~36000 - * sq = (_(x) -> x*x); profile_expr(my_map(l(1,2,3), sq)); // => ~36000 - * profile_expr(map(l(1,2,3), _*_)); // => ~80000 - * - *- *
return(expr?)Sometimes its convenient to break the organized control flow, or it is not practical to pass - * the final result value of a function to the last statement, in this case a return statement can be used
- *If no argument is provided - returns null value.
- *- * def() -> ( - * expr1; - * expr2; - * return(expr3); // function terminates returning expr3 - * expr4; // skipped - * expr5 // skipped - * ) - *- *
In general its cheaper to leave the last expression as a return value, rather than calling returns everywhere, - * but it would often lead to a messy code.
- *exit(expr?)It terminates entire program passing expr as the result of the program execution, or null if omitted.
try(expr, catch_expr(_)?) ... throw(value?)try function evaluates expression, and continues further unless throw function is called
- * anywhere inside expr. In that case the catch_expr is evaluates with _ set
- * to the argument throw was called with.
- * This mechanic accepts skipping thrown value - it throws null instead, and catch expression - then try returns null as well
- * This mechanism allows to terminate large portion of a convoluted
- * call stack and continue program execution. There is only one level of exceptions currently in carpet, so if the inner
- * function also defines the try catchment area, it will received the exception first, but it can technically
- * rethrow the value its getting for the outer scope. Unhandled throw acts like an exit statement.
if(cond, expr, cond?, expr?, ..., default?)If statement is a function that takes a number of conditions that are evaluated one after another and if
- * any of them turns out true, its expr gets returned, otherwise, if all conditions fail, the return value is
- * default expression, or null if default is skipped
if function is equivalent to if (cond) expr; else if (cond) expr; else default;
- * from Java, just in a functional form
There is a number of operators you can use inside the expressions. Those could be considered
- * generic type operators that apply to most data types. They also follow standard operator
- * precedence, i.e. 2+2*2 is understood as 2+(2*2),
- * not (2+2)*2, otherwise they are applied from left to right, i.e.
- * 2+4-3 is interpreted as (2+4)-3, which in case of numbers
- * doesn't matter, but since scarpet allows for mixing all value types
- * the associativity would matter, and may lead to unintended effects:
Important operator is function definition -> operator. It will be covered
- * in {@link carpet.script.Expression#UserDefinedFunctionsAndControlFlow}
- * '123'+4-2 => ('123'+4)-2 => '1234'-2 => '134'
- * '123'+(4-2) => '123'+2 => '1232'
- * 3*'foo' => 'foofoofoo'
- * 1357-5 => 1352
- * 1357-'5' => 137
- * 3*'foo'-'o' => 'fff'
- * l(1,3,5)+7 => l(8,10,12)
- *
- * As you can see, values can behave differently when mixed with other types
- * in the same expression. in case values are of the same types, the result
- * tends to be obvious, but Scarpet tries to make sense of whatever it
- * has to deal with
- * Here is the complete list of operators in scarpet including control flow operators.
- * Note, that commas and brackets are not technically operators, but part of the language,
- * even if they look like them:
- *
~ :+ - !^* / %+ -== != > >= <= <&&||= += <>->;,( )Get, Accessor Operator :Operator version of the get(...) function to access elements of lists, maps, and potentially other
- * containers (i.e. NBTs). It is important to distinguish from ~ operator, which is a matching operator,
- * which is expected to perform some extra computations to retrieve the result, while : should be
- * straightforward and immediate, and the source object should behave like a container and support full container
- * API, meaning get(...), put(...), delete(...),
- * and has(...) functions
For certain operators and functions (get, put, delete, has, =, +=) objects can use : annotated
- * fields as l-values, meaning construct like foo:0 = 5, would act like put(foo, 0, 5),
- * rather than get(foo, 0) = 5, which would result in an error.
TODO: add more information about l-value behaviour.
- * - *Matching Operator ~This operator should be understood as 'matches', 'contains', 'is_in',
- * or 'find me some stuff about something else. For strings it matches the right operand as a regular
- * expression to the left, returning the first match. This can be used to extract information from unparsed nbt's
- * in a more convoluted way (use get(...) for more appropriate way of doing it).
- * For lists it checks if an element is in the list, and returns the index of that element,
- * or null if no such element was found, especially that the use of first(...) function will not
- * return the index. Currently it doesn't have any special behaviour for numbers - it checks for existence of characters
- * in string representation of the left operand with respect of the regular expression on the right hand side.
- * string
in Minecraft API portion entity ~ feature is a shortcode for query(entity,feature)
- * for queries that do not take any extra arguments.
- * l(1,2,3) ~ 2 => 1
- * l(1,2,3) ~ 4 => null
- * 'foobar' ~ '.b' => 'ob'
- * player('*') ~ 'gnembon' // null unless player gnembon is logged in (better to use player('gnembon') instead
- * p ~ 'sneaking' // if p is an entity returns whether p is sneaking
- *
- * Or a longer example of an ineffective way to searching for a squid
- *
- * entities = entities_area('all',x,y,z,100,10,100);
- * sid = entities ~ 'Squid';
- * if(sid != null, run('execute as '+query(get(entities,sid),'id')+' run say I am here '+query(get(entities,sid),'pos') ) )
- *
- * Or an example to find if a player has specific enchantment on a held axe (either hand) and get its level
- * (not using proper NBTs query support via get(...)):
- * global_get_enchantment(p, ench) -> (
- * $ for(l('main','offhand'),
- * $ holds = query(p, 'holds', _);
- * $ if( holds,
- * $ l(what, count, nbt) = holds;
- * $ if( what ~ '_axe' && nbt ~ ench,
- * $ lvl = max(lvl, number(nbt ~ '(?<=lvl:)\\d') )
- * $ )
- * $ )
- * $ );
- * $ lvl
- * $);
- * /script run global_get_enchantment(players(), 'sharpness')
- *
- *
- * Basic Arithmetic Operators + - * /Allows to add the results of two expressions. If the operands resolve to numbers, the result is
- * arithmetic operation.
- * In case of strings, adding or subtracting from a string results in string concatenation and
- * removal of substrings from that string. Multiplication of strings and numbers results in repeating the
- * string N times and division results in taking the first k'th part of the string, so that str*n/n ~ str
- * In case first operand is a list, either it results in a new list
- * with all elements modified one by one with the other operand, or if the operand is a list with the same number of
- * items - elementwise addition/subtraction
Examples:
- *- * 2+3 => 5 - * 'foo'+3+2 => 'foo32' - * 'foo'+(3+2) => 'foo5' - * 3+2+'bar' => '5bar' - * 'foo'*3 => 'foofoofoo' - * 'foofoofoo' / 3 => 'foo' - * 'foofoofoo'-'o' => 'fff' - * l(1,2,3)+1 => l(2,3,4) - * b = l(100,63,100); b+l(10,0,10) => l(110,63,110) - *- * - *
Just Operators % ^The modulo and exponent (power) operators work only if both operands are numbers
- *- * pi^pi%euler => 1.124.... - * -9 % 4 => -1 - * 9 % -4 => 0 ¯\_(ツ)_/¯ Java - * -3 ^ 2 => 9 - * -3 ^ pi => // Error - *- * - *
Comparison Operators == != < > <= >=Allows to compare the results of two expressions.
- * For numbers it is considers arithmetic order of numbers, for strings - lexicographical,
- * nulls are always 'less' than everything else, and lists check their elements - if the sizes
- * are different, the size matters, otherwise, pairwise comparisons for each elements are performed.
- * The same order rules than with all these operators are used with the default sortographical order as
- * used by sort function. All of these are true:
- *
- * null == null - * null != false - * 0 == false - * 1 == true - * null < 0 - * null < -1000 - * 1000 < 'a' - * 'bar' < 'foo' - * 3 == 3.0 - *- * - *
Logical Operators && ||These operator compute respective boolean operation on the operands. What it important is that if calculating
- * of the second operand is not necessary, it won't be evaluated, which means one can use them as conditional
- * statements. In case of success returns first positive operand (||) or last one (&&).
- * true || false => 1
- * null || false => 0
- * null != false || run('kill gnembon') => 1 // gnembon survives
- * null != false && run('kill gnembon') => 0 // when cheats not allowed
- * null != false && run('kill gnembon') => 1 // gnembon dies, cheats allowed
- *
- *
-
- * Assignment Operators = <> +=A set of assignment operators. All require bounded variable on the LHS, <> requires
- * bounded arguments on the right hand side as well (bounded, meaning being variables). Additionally they can also
- * handle list constructors with all bounded variables, and work then as list assignment operators.
- * When += is used on a list, it extends that list of that element, and returns the list (old == new).
- * scarpet doesn't support currently removal of items. Removal of items can be obtaine via
- * filter command, and reassigning it fo the same variable. Both operations would require rewriting of the
- * array anyways.
- * a = 5 => a == 5 - * l(a,b,c) = l(3,4,5) => a==3, b==4, c==5 - * l(minx,maxx) = sort(xi,xj); // minx assumes min(xi, xj) and maxx, max(xi, xj) - * l(a,b,c,d,e,f) = l(range(6)); l(a,b,c) <> l(d,e,f); l(a,b,c,d,e,f) => [3,4,5,0,1,2] - * a = l(1,2,3); a += 4 => [1,2,3,4] - * a = l(1,2,3,4); a = filter(a,_!=2) => [1,3,4] - *- *
Unary Operators - +Require a number, flips the sign. One way to assert it's a number is by crashing the script. gg.
- *- * -4 => -4 - * +4 => 4 - * +'4' // Error message - *- * - *
Negation Operator !flips boolean condition of the expression. Equivalent of bool(expr)==false
- * !true => 0 - * !false => 1 - * !null => 1 - * !5 => 0 - * !l() => 1 - * !l(null) => 0 - *- *
There is bunch of them - they require a number and spit out a number, - * doing what you would expect them to do.
- *fact(n)Factorial of a number, a.k.a n!, just not in scarpet. Gets big... quick...
sqrt(n)Square root. For other fancy roots, use ^, math and yo noggin. Imagine square roots on a tree...
abs(n)Absolut value.
- *round(n)Closest integer value. Did you know the earth is also round?
- *floor(n)Highest integer that is still no larger then n. Insert a floor pun here.
ceil(n)First lucky integer that is not smalller than n. As you would expect, ceiling is typically
- * right above the floor.
ln(n)Natural logarithm of n. Naturally.
ln1p(n)Natural logarithm of n+1. Very optimistic.
log10(n)Decimal logarithm of n. Its ceiling is the length of its floor.
log(n)Binary logarithm of n. Finally, a proper one, not like the previous 11.
log1p(n)Binary logarithm of n+1. Also always positive.
mandelbrot(a, b, limit)Computes the value of the mandelbrot set, for set a and b spot.
- * Spot the beetle. Why not.
min(arg, ...), min(list), max(arg, ...), max(list)Compute minimum or maximum of supplied arguments assuming default sorthoraphical order. In case you are
- * missing argmax, just use a ~ max(a), little less efficient, but still fun.
- *
- * Interesting bit - min and max don't remove variable associations from arguments, which
- * means can be used as LHS of assignments (obvious case), or argument spec in function definitions (far less obvious).
- *
- * a = 1; b = 2; min(a,b) = 3; l(a,b) => [3, 2] - * a = 1; b = 2; fun(x, min(a,b)) -> l(a,b); fun(3,5) => [5, 0] - *- *
Absolutely no idea, how the latter might be useful in practice. But since it compiles, can ship it.
- * - *relu(n)Linear rectifier of n. 0 below 0, n above. Why not. max(0,n)
- * with less moral repercussions.
sin(x)cos(x)tan(x)asin(x)acos(x)atan(x)atan2(x,y)sinh(x)cosh(x)tanh(x)sec(x)csc(x)sech(x)csch(x)cot(x)acot(x)coth(x)asinh(x)acosh(x)atanh(x)rad(deg)deg(rad)Use as you wish
- * - *Efficient use of these functions can greatly simplify your programs and speed them up, as these functions
- * will internalize most of the operations that need to be applied on multiple values at the same time. Most
- * of them take a list argument which can be any iterable structure in scarpet, including
- * generators, like rect, or range, and maps, where the iterator returns all the map keys
break(), break(expr), continue(), continue(expr)These allow to control execution of a loop either skipping current iteration code, using continue, or finishing
- * the current loop, using break. break and continue can only be used inside
- * for, while, loop, map, filter and reduce functions, while break can be used in first as well.
- * Outside of the internal expressions of these functions, calling break or continue will cause an
- * error. In case of the nexted loops, and more complex setups, use custom try and throw setup.
Please check corresponding loop function description what continue and break do in their contexts,
- * but in general case, passed values to break and continue will be used in place of the return value of the
- * internal iteration expression.
for(list,expr(_,_i))Evaluates expression over list of items from the list. Supplies
- * _(value) and _i(iteration number) to the expr.
Returns the number of times expr was successful. Uses continue and break argument
- * in place of the returned value from the expr(if supplied), to determine if the iteration was successful.
- * check_prime(n) -> !first( range(2, sqrt(n)+1), !(n % _) ); - * for(range(1000000,1100000),check_prime(_)) => 7216 - *- *
From which we can learn that there is 7216 primes between 1M and 1.1M
- * - *while(cond, limit)Evaluates expression expr repeatedly until condition cond becomes false,
- * but not more than limit times. Returns the result of the last expr evaluation,
- * or null if nothing was successful. Both expr and cond will recveived a
- * bound variable _ indicating current iteration, so its a number.
- * while(a<100,10,a=_*_) => 81 // loop exhausted via limit - * while(a<100,20,a=_*_) => 100 // loop stopped at condition, but a has already been assigned - * while(_*_<100,20,a=_*_) => 81 // loop stopped at condition, before a was assigned a value - *- * - *
loop(num,expr(_),exit(_)?)Evaluates expression expr, num number of times.
- *expr receives _ system variable indicating the iteration.
- * loop(5, game_tick()) => repeat tick 5 times - * list = l(); loop(5, x = _; loop(5, list += l(x, _) ) ); list - * // double loop, produces: [[0, 0], [0, 1], [0, 2], [0, 3], [0, 4], [1, 0], [1, 1], ... , [4, 2], [4, 3], [4, 4]] - *- *
In this small example we will search for first 10 primes, apparently including 0:
- *- * check_prime(n) -> !first( range(2, sqrt(n)+1), !(n % _) ); - * primes = l(); - * loop(10000, if(check_prime(_), primes += _ ; if (length(primes) >= 10, break()))); - * primes - * - * // outputs: [0, 1, 2, 3, 5, 7, 11, 13, 17, 19] - *- * - *
map(list,expr(_,_i))Converts a list of values, to another list where each value is result of an expression
- * v = expr(_, _i) where _ is passed as each element of the list, and _i is
- * the index of such element. If break is called the map returns whatever collected thus far. If
- * continue and break are used with supplied argument, it is used in place of the resulting
- * map element, otherwise current element is skipped.
- * map(range(10), _*_) => [0, 1, 4, 9, 16, 25, 36, 49, 64, 81]
- * map(players('*'), _+' is stoopid') [gnembon is stoopid, herobrine is stoopid]
- *
- *
- * filter(list,expr(_,_i))filters list elements returning only these that return positive result of the expr.
- * With break and continue statements, the supplied value can be used as a boolean check instead.
- * filter(range(100), !(_%5), _*_>1000) => [0, 5, 10, 15, 20, 25, 30]
- * map(filter(entity_list('*'),_=='Witch'), query(_,'pos') ) => [[1082.5, 57, 1243.5]]
- *
- *
- * first(list,expr(_,_i))Finds and returns the first item in the list that satisfies expr. It sets _ for current element value,
- * and _i for index of that element. break can be called inside the iteration code, using its argument
- * value instead of the current item. continue has no sense and cannot be called inside first call.
- * first(range(1000,10000), n=_; !first( range(2, sqrt(n)+1), !(n % _) ) ) => 1009 // first prime after 1000 - *- *
Notice in the example above, that we needed to rename the outer _ to be albe to use in in the inner
- * first call
all(list,expr(_,_i))Returns true if all elements on the list satisfy the condition. Its roughly equivalent to
- * all(list,expr) <=> for(list,expr)==length(list). expr
- * also receives bound _ and _i variables. break and continue have no sense
- * and cannot be used inside of expr body.
- * all([1,2,3], check_prime(_)) => 1 - * all(neighbours(x,y,z), _=='stone') => 1 // if all neighbours of [x, y, z] are stone - * map(filter(rect(0,4,0,1000,0,1000), l(x,y,z)=pos(_); all(rect(x,y,z,1,0,1),_=='bedrock') ), pos(_) ) - * => [[-298, 4, -703], [-287, 4, -156], [-269, 4, 104], [242, 4, 250], [-159, 4, 335], [-208, 4, 416], [-510, 4, 546], [376, 4, 806]] - * // find all 3x3 bedrock structures in the top bedrock layer - * map( filter( rect(0,4,0,1000,1,1000,1000,0,1000), l(x,y,z)=pos(_); - * all(rect(x,y,z,1,0,1),_=='bedrock') && for(rect(x,y-1,z,1,1,1,1,0,1),_=='bedrock')<8), - * pos(_) ) => [[343, 3, -642], [153, 3, -285], [674, 3, 167], [-710, 3, 398]] - * // ditto, but requiring at most 7 bedrock block in the 18 blocks below them - *- * - *
reduce(list,expr(_a,_,_i), initial)Applies expr for each element of the list and saves the result in _a accumulator.
- * Consecutive calls to expr can access that value to apply more values. You also need to specify
- * the initial value to apply for the accumulator. break can be used to terminate reduction prematurely.
- * If a value is provided to break or continue, it will be used from now on as a new value for the
- * accumulator.
- * reduce([1,2,3,4],_a+_,0) => 10 - * reduce([1,2,3,4],_a*_,1) => 24 - *- *
Scarpet supports basic container types: lists and maps (aka hashmaps, dicts etc..)
- *Here is a list of operations that work on all types of containers: lists, maps, as well as other Minecraft - * specific modifyable containers, like NBTs
- * - *get(container, address, ...), get(lvalue), ':' operatorReturns the value at address element from the value.
- * For lists it indicates an index, use negative numbers to reach elements from the end of the list. get
- * call will always be able to find the index. In case there is few items, it will loop over
for maps, retrieves the value under the key specified in the address or null otherwise
[Minecraft specific usecase]: In case value is of nbt type, uses address as the
- * nbt path to query,
- * returning null, if path is not found, one value if there was one match, or list of values if result is a list.
- * Returned elements can be of numerical type, string texts, or another compound nbt tags
In case to simplify the access with nested objects, you can add chain of addresses to the arguments of
- * get rather than calling it multiple times. get(get(foo,a),b) is equivalent to
- * get(foo, a, b), or foo:a:b.
- * get(l(range(10)), 5) => 5
- * get(l(range(10)), -1) => 9
- * get(l(range(10)), 10) => 0
- * l(range(10)):93 => 3
- *
- * get(player() ~ 'nbt', 'Health') => 20 // inefficient way to get player health, use player() ~ 'health' instead
- *
- * get(m( l('foo',2), l('bar',3), l('baz',4) ), 'bar') => 3
- *
- *
- * has(container, address, ...), has(lvalue)Similar to get, but returns boolean value indicating if the given index / key / path is in the
- * container. Can be used to determine if get(...)==null means the element doesn't exist, or the stored value
- * for this address is null, and is cheaper to run than get.
Like get, it can accept multiple addresses for chains in nested containers. In this case has(foo:a:b)
- * is equivalent to has(get(foo,a), b) or has(foo, a, b)
delete(container, address, ...), delete(lvalue)Removes specific entry from the container. For the lists - removes the element and shrinks it. For maps, it - * removes the key from the map, and for nbt - removes content from a given path. For lists and maps returns previous - * entry at the address, for nbt's - number of removed objects, with 0 indicating that the original value was unaffected.
- *Like with the get and has, delete can accept chained addresses, as well as
- * l-value container access, removing the value
- * from the leaf of the path provided, so delete(foo, a, b) is the same as delete(get(foo,a),b)
- * or delete(foo:a:b)
Returns true, if container was changed, false, if it was left unchanged, and null if operation was invalid.
- * - *put(container, address, value), put(container, address, value, mode), put(lvalue, value)Lists
- *Modifies the container by replacing the value under the address with the supplied value.
- * For lists, a valid index is required, but can be negative as well to indicate positions from the end of the list.
- * If null is supplied as the address, it always means - add to the end of the list.
There are three modes that lists can have items added to them: - *
replace(default): Replaces item under given index(address). Doesn't change the size of the array
- * unless null address is used, which is an exception and then it appends to the endinsert: Inserts given element at a specified index, shifting the rest of the array to make space
- * for the item. Note that index of -1 points to the last element of the list, thus inserting at that position and
- * moving the previous last element to the new last element position. To insert at the end, use +=
- * operator, or null address in putextend: treats the supplied value as an iterable set of values to insert at a given index,
- * extending the list by this amount of items. Again use null address/index to point to the end of
- * the listDue to the extra mode parameter, there is no chaining for put, but you can still use l-value
- * container access to indicate container and address, so put(foo, key, value) is the same as
- * put(foo:key, value) or foo:key=value
Returns true, if container got modified, false otherwise, and null if operation was invalid.
- * - *Maps
- *For maps there are no modes available (yet, seems there is no reason to). It replaces the value under the supplied - * key (address), or sets it if not currently present.
- *NBT Tags
- *
- * The address for nbt values is a valid nbt path that you would use with /data command, and tag is any
- * tag that would be applicable for a given insert operation. Note that to distinguish between proper types (like integer
- * types, you need to use command notation, i.e. regular ints is 123, while byte size int would be 123b
- * and an explicit string would be "5", so it helps that scarpet uses single quotes in his strings. Unlike
- * for lists and maps, it returns the number of affected nodes, or 0 if none were affected.
- *
There are three modes that NBT tags can have items added to them: - *
replace(default): Replaces item under given path(address). Removes them first if possible, and then
- * adds given element to the supplied position. The target path can indicate compound tag keys, lists, or individual
- * elements of the lists.<N>: Index for list insertions. Inserts given element at a specified index, inside a list
- * specified with the path address. Fails if list is not specified. It behaves like insert mode for lists,
- * i.e. it is not removing any of the existing elements. Use replace to remove and replace existing element.
- * merge: assumes that both path and replacement target are of compound type (dictionaries, maps,
- * {} types), and merges keys from value with the compound tag under the path
- * a = l(1, 2, 3); put(a, 1, 4); a => [1, 4, 3]
- * a = l(1, 2, 3); put(a, null, 4); a => [1, 2, 3, 4]
- * a = l(1, 2, 3); put(a, 1, 4, 'insert'); a => [1, 4, 2, 3]
- * a = l(1, 2, 3); put(a, null, l(4, 5, 6), 'extend'); a => [1, 2, 3, 4, 5, 6]
- * a = l(1, 2, 3); put(a, 1, l(4, 5, 6), 'extend'); a => [1, 4, 5, 6, 2, 3]
- * a = l(l(0,0,0),l(0,0,0),l(0,0,0)); put(a.1, 1, 1); a => [[0, 0, 0], [0, 1, 0], [0, 0, 0]]
- * a = m(1,2,3,4); put(a, 5, null); a => {1: null, 2: null, 3: null, 4: null, 5: null}
- * tag = nbt('{}'); put(tag, 'BlockData.Properties', '[1,2,3,4]'); tag => {BlockData:{Properties:[1,2,3,4]}}
- * tag = nbt('{a:[{lvl:3},{lvl:5},{lvl:2}]}'); put(tag, 'a[].lvl', 1); tag => {a:[{lvl:1},{lvl:1},{lvl:1}]}
- * tag = nbt('{a:[{lvl:[1,2,3]},{lvl:[3,2,1]},{lvl:[4,5,6]}]}'); put(tag, 'a[].lvl', 1, 2); tag
- * => {a:[{lvl:[1,2,1,3]},{lvl:[3,2,1,1]},{lvl:[4,5,1,6]}]}
- * tag = nbt('{a:[{lvl:[1,2,3]},{lvl:[3,2,1]},{lvl:[4,5,6]}]}'); put(tag, 'a[].lvl[1]', 1); tag
- * => {a:[{lvl:[1,1,3]},{lvl:[3,1,1]},{lvl:[4,1,6]}]}
- *
- *
- * l(values ...), l(iterator) Creates a list of values of the expressions passed as parameters. It can be used as an L-value and if all
- * elements are variables, you coujld use it to return multiple results from one function call, if that function returns
- * a list of results with the same size as the l call uses. In case there is only one argument and it is
- * an iterator (vanilla expression specification has range, but Minecraft API implements
- * a bunch of them, like diamond), it will convert it to a proper list. Iterators can only be used in
- * high order functions, and are treated as empty lists, unless unrolled with l
- * l(1,2,'foo') => [1, 2, foo] - * l() => [] (empty list) - * l(range(10)) => [0, 1, 2, 3, 4, 5, 6, 7, 8, 9] - * l(1, 2) = l(3, 4) => Error: l is not a variable - * l(foo, bar) = l(3,4); foo==3 && bar==4 => 1 - * l(foo, bar, baz) = l(2, 4, 6); l(min(foo, bar), baz) = l(3, 5); l(foo, bar, baz) => [3, 4, 5] - *- *
In the last example l(min(foo, bar), baz) creates a valid L-value, as min(foo, bar) finds the
- * lower of the variables (in this case foo) creating a valid assignable L-list of [foo, baz], and these
- * values will be assigned new values
join(delim, list), join(delim, values ...) Returns a string that contains joined elements of the list, iterator, or all values, concatenated with delim delimiter
- * join('-',range(10)) => 0-1-2-3-4-5-6-7-8-9
- * join('-','foo') => foo
- * join('-', 'foo', 'bar') => foo-bar
- *
- *
- * split(delim, expr)Splits a string undr expr by delim which can be a regular expression
- * split('',foo) => [f, o, o]
- * split('.','foo.bar') => []
- * split('\\.','foo.bar') => [foo, bar]
- *
- *
- * slice(expr, from, to?)extracts a substring, or sublist (based on the type of the result of the expression under expr with starting index
- * of from, and ending at to if provided, or the end, if omitted
- * slice(l(0,1,2,3,4,5), 1, 3) => [1, 2, 3]
- * slice('foobar', 0, 1) => 'f'
- * slice('foobar', 3) => 'bar'
- * slice(range(10), 3, 5) => [3, 4, 5]
- * slice(range(10), 5) => [5, 6, 7, 8, 9]
- *
- *
- * sort(list), sort(values ...) Sorts in the default sortographical order either all arguments, or a list if its the only argument. It returns a new - * sorted list, not affecting the list passed to the argument
- *
- * sort(3,2,1) => [1, 2, 3]
- * sort('a',3,11,1) => [1, 3, 11, 'a']
- * list = l(4,3,2,1); sort(list) => [1, 2, 3, 4]
- *
- *
- * sort_key(list, key_expr)Sorts a copy of the list in the order or keys as defined by the key_expr for each element
- * sort_key([1,3,2],_) => [1, 2, 3] - * sort_key([1,3,2],-_) => [3, 2, 1] - * sort_key(l(range(10)),rand(1)) => [1, 0, 9, 6, 8, 2, 4, 5, 7, 3] - * sort_key(l(range(20)),str(_)) => [0, 1, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 2, 3, 4, 5, 6, 7, 8, 9] - *- * - *
range(to), range(from, to), range(from, to, step)Creates a range of numbers from from, no greater/larger than to.
- * The step parameter dictates not only the increment size, but also direction (can be negative).
- * The returned value is not a proper list, just the iterator
- * but if for whatever reason you need a proper list with all items evaluated, use l(range(to)).
- * Primarily to be used in higher order functions
- * range(10) => [...] - * l(range(10)) => [0, 1, 2, 3, 4, 5, 6, 7, 8, 9] - * map(range(10),_*_) => [0, 1, 4, 9, 16, 25, 36, 49, 64, 81] - * reduce(range(10),_a+_, 0) => 45 - * range(5,10) => [5, 6, 7, 8, 9] - * range(20, 10, -2) => [20, 18, 16, 14, 12] - *- * - *
element(list, index)(deprecated)Legacy support for older method that worked only on lists. Please use get(...) for equivalent
- * support, or . operator. Also previous unique behaviours with put on lists has been
- * removed to support all type of container types.
Scarpet supports map structures, aka hashmaps, dicts etc. Map structure can also be used, with null
- * values as sets. Apart from container access functions, (. , get, put, has, delete),
- * the following functions:
m(values ...), m(iterator), m(key_value_pairs) creates and initializes a map with supplied keys, and values. If the arguments contains a flat list, - * these are all treated as keys with no value, same goes with the iterator - creates a map that behaves like a set. - * If the arguments is a list of lists, they have to have two elements each, and then first is a key, and second, - * a value
- *
- * m(1,2,'foo') => {1: null, 2: null, foo: null}
- * m() => {} (empty map)
- * m(range(10)) => {0: null, 1: null, 2: null, 3: null, 4: null, 5: null, 6: null, 7: null, 8: null, 9: null}
- * m(l(1, 2), l(3, 4)) => {1: 2, 3: 4}
- * reduce(range(10), put(_a, _, _*_); _a, m())
- * => {0: 0, 1: 1, 2: 4, 3: 9, 4: 16, 5: 25, 6: 36, 7: 49, 8: 64, 9: 81}
- *
- * keys(map), values(map), pairs(map) Returns full lists of keys, values and key-value pairs (2-element lists) for all the entries in the map
- * - *copy(expr)Returns the deep copy of the expression. Can be used to copy mutable objects, like maps and lists
- *type(expr)Returns the string value indicating type of the expression. Possible outcomes are
- * null, number, string, list, iterator, as well as minecraft related concepts like
- * block, entity, nbt
bool(expr)Returns a boolean context of the expression. Note that there are no true/false values in
- * scarpet. true is alias of 1, and false is 0. Bool is also interpreting
- * string values as boolean, which is different from other places where boolean context can be used.
- * This can be used in places where API functions return string values to represent binary values
- * bool(pi) => 1
- * bool(false) => 0
- * bool('') => 0
- * bool(l()) => 0
- * bool(l('')) => 1
- * bool('foo') => 1
- * bool('false') => 0
- * bool('nulL') => 0
- * if('false',1,0) => 1
- *
- *
- * number(expr)Returns a numeric context of the expression. - * Can be used to read numbers from strings
- *
- * number(null) => null
- * number(false) => 0
- * number('') => null
- * number('3.14') => 3.14
- * number(l()) => 0
- * number(l('')) => 1
- * number('foo') => null
- * number('3bar') => null
- * number('2')+number('2') => 4
- *
- *
- * str(expr, params? ... ), str(expr, param_list)Returns a formatted string representing expression.
- * Accepts formatting style accepted by String.format.
- * Supported types (with "%?" syntax):
- * str(null) => null
- * str(false) => 0
- * str('') => null
- * str('3.14') => 3.14
- * str(l()) => 0
- * str(l('')) => 1
- * str('foo') => null
- * str('3bar') => null
- * str(2)+str(2) => 22
- * str('pi: %.2f',pi) => 'pi: 3.14'
- * str('player at: %d %d %d',pos(player())) => 'player at: 567, -2423, 124'
- *
- *
- * Scarpet allows to run threads of execution in parallel to the main script execution thread. In Minecraft, the main
- * thread scripts are executed on the main server thread. Since Minecraft is inherently NOT thread safe, it is not that
- * beneficial to parallel execution in order to access world resources faster. Both
- * GetBlockState and setBlockState are not thread safe and require the execution to park on the server thread,
- * where these requests can be executed in the off-tick time in between ticks that didn't take 50ms. There are however
- * benefits of running things in parallel, like fine time control not relying on the tick clock, or running things independent
- * on each other. You can still run your actions on tick-by-tick basis, either taking control of the execution using
- * game_tick() API function (nasty solution), or scheduling tick using schedule() function (much nicer solution),
- * but threading often gives the neatest solution to solve problems in parallel (see scarpet camera).
- *
Due to limitations with the game, there are some limits to the threading as well. You cannot for instance join_task() at all
- * from the main script and server thread, because any use of Minecraft specific function that require any world access, will
- * require to park and join on the main thread to get world access, meaning that calling join on that task would inevitably lead to a
- * typical deadlock. You can still join tasks from other threads, just because the only possibility of a deadlock in this case would
- * come explicitly from your bad code, not the internal world access behaviour. Some things tough like player or entity manipulation,
- * can be effectively parallelized.
task(function, ?args...., ?executor)Creates and runs a parallel task, returning the handle to the task object. Task will return the return value of the function
- * when its completed, or will return null immediately if task is still in progress, so grabbing a value of
- * a task object is non-blocking. Function can be either function value, or function lambda, or a name of an existing defined function.
- * In case function needs arguments to be called with, they should be supplied after the function name, or value.
- * Optional executor identifier is to place the task in a specific queue identified by this value. The default
- * thread value is the null thread. There is no limits on number of parallel tasks for any executor, so using different queues is solely
- * for synchronization purposes. Also, since task function knows how many extra arguments it requires, the use of
- * tailing optional parameter for the custom executor thread pool is not ambiguous.
- *
- * task( _() -> print('Hello Other World') ) => Runs print command on a separate thread
- * foo(a, b) -> print(a+b); task('foo',2,2) => Uses existing function definition to start a task
- * task('foo',3,5,'temp'); => runs function foo with a different thread executor, identified as 'temp'
- * a = 3; task( _(outer(a), b) -> foo(a,b), 5, 'temp') => Another example of running the same thing passing arguments using closure over anonymous function as well as passing a parameter.
- *
- * task_count(executor?)If no argument provided, returns total number of tasks being executed in parallel at this moment using scarpet threading system.
- * If the executor is provided, returns number of active tasks for that provider. Use task_count(null) to
- * get the task count of the default executor only.
task_value(task)Returns the task return value, or null if task hasn't finished yet. Its a non-blocking operation.
- * Unlike join_task, can be called on any task at any point
task_join(task)Waits for the task completion and returns its computed value. If the task has already finished returns it immediately.
- * Unless taking the task value directly, i.e. via task_value, this operation is blocking. Since Minecraft has
- * a limitation that all world access operations have to be performed on the main game thread in the off-tick time, joining any tasks that use
- * Minecraft API from the main thread would mean automatic lock, so joining from the main thread is not allowed.
- * Join tasks from other threads, if you really need to, or communicate asynchronously with the task via globals or
- * function data / arguments to monitor its progress, communicate, get partial results, or signal termination.
task_completed(task)Returns true if task has completed, or false otherwise.
- * - *synchronize(lock, expression)Evaluates expression synchronized with respect to the lock lock. Returns the value of the
- * expression.
lower(expr), upper(expr), title(expr)Returns lowercase, uppercase or titlecase representation of a string representation of the passed expression
- *
- * lower('aBc') => 'abc'
- * upper('aBc') => 'ABC'
- * title('aBc') => 'Abc'
- *
- *
- * replace(string, regex, repl?); replace_first(string, regex, repl?)Replaces all, or first occurence of a regular expression in the string with repl expression, or
- * nothing, if not specified
- * replace('abbccddebfg','b+','z') // => azccddezfg
- * replace_first('abbccddebfg','b+','z') // => azccddebfg
- *
- *
- * length(expr)Returns length of the expression, the length of the string, - * the length of the integer part of the number, or length of the list
- *
- * length(pi) => 1
- * length(pi*pi) => 1
- * length(pi^pi) => 2
- * length(l()) => 0
- * length(l(1,2,3)) => 3
- * length('') => 0
- * length('foo') => 3
- *
- *
- * rand(expr), rand(expr, seed)returns a random number from 0.0
- * (inclusive) to expr (exclusive).
- * In boolean context (in conditions, boolean functions, or bool), returns
- * false if the randomly selected value is less than 1. This means that rand(2) returns true half
- * of the time and rand(5) returns true for 80% (4/5) of the time. If seed is not provided, uses a random seed.
- * If seed is provided, each consecutive call to rand() will act like 'next' call to the same random object.
- * Scarpet keeps track of up to 1024 custom random number generators, so if you exceed this number (per app), then your
- * random sequence will revert to the beginning.
- * map(range(10), floor(rand(10))) => [5, 8, 0, 6, 9, 3, 9, 9, 1, 8]
- * map(range(10), bool(rand(2))) => [1, 1, 1, 0, 0, 1, 1, 0, 0, 0]
- * map(range(10), str('%.1f',rand(_))) => [0.0, 0.4, 0.6, 1.9, 2.8, 3.8, 5.3, 2.2, 1.6, 5.6]
- *
- *
- * perlin(x), perlin(x, y), perlin(x, y, z), perlin(x, y, z, seed)returns a noise value from 0.0 to 1.0 (roughly) for 1, 2 or 3 dimensional coordinate.
- * The default seed it samples from is 0, but seed can be
- * specified as a 4th argument as well. In case you need 1D or 2D noise values with custom seed, use null
- * for z, or y and z arguments respectively.
Perlin noise is based on a square grid and generates rougher maps comparing to Simplex, which is creamier. - * Querying for lower-dimensional result, rather than - * affixing unused dimensions to constants has a speed benefit, - *
- *Thou shall not sample from noise changing seed frequently. Scarpet will keep track of the last 256 perlin seeds used for sampling
- * providing similar speed comparing to the default seed of 0. In case the app engine uses more than 256 seeds at the same time,
- * switching between them can get much more expensive.
simplex(x, y), simplex(x, y, z), simplex(x, y, z, seed)returns a noise value from 0.0 to 1.0 (roughly) for 2 or 3 dimensional coordinate.
- * The default seed it samples from is 0, but seed can be
- * specified as a 4th argument as well. In case you need 2D noise values with custom seed, use null
- * for z argument.
Simplex noise is based on a triangular grid and generates smoother maps comparing to Perlin. - * To sample 1D simplex noise, affix other coordinate to a constant. - *
- *Thou shall not sample from noise changing seed frequently. Scarpet will keep track of the last 256 simplex seeds used for sampling
- * providing similar speed comparing to the default seed of 0. In case the app engine uses more than 256 seeds at the same time,
- * switching between them can get much more expensive.
print(expr)prints the value of the expression to chat.
- * Passes the result of the argument to the output unchanged, so print-statements can
- * be weaved in code to debug programming issues
- * print('foo') => results in foo, prints: foo
- * a = 1; print(a = 5) => results in 5, prints: 5
- * a = 1; print(a) = 5 => results in 5, prints: 1
- * print('pi = '+pi) => prints: pi = 3.141592653589793
- * print(str('pi = %.2f',pi)) => prints: pi = 3.14
- *
- *
- * sleep(expr)Halts the execution of the program (and the game itself) for expr milliseconds.
- * All in all, its better to use game_tick(expr) to let the game do its job while the program waits
sleep(50)- *
time()Returns the number of milliseconds since 'some point',
- * like Java's System.nanoTime(). It returns a float, which has 1 microsecond precision
- * (0.001 ms)
- * start_time = time();
- * flip_my_world_upside_down();
- * print(str('this took %d milliseconds',time()-start_time))
- *
- *
- * profile_expr(expression)Returns number of times given expression can be run in 50ms time. Useful to profile and optimize your - * code. Note that, even if its only a number, it WILL run these commands, so if they are destructive, - * you need to be careful.
- * - *var(expr)Returns the variable under the name of the string value of the expression. Allows to - * manipulate variables in more programmatic manner, which allows to use local variable set with a - * hash map type key-value access, can also be used with global variables
- *
- * a = 1; var('a') = 'foo'; a => a == 'foo'
- *
- *
- * undef(expr)Removes all bindings of a variable with a name of expr.
- * Removes also all function definitions with that name. It can affect global variable pool, and local variable set
- * for a particular function which will become invalid ........,
- * inc(i) -> i+1; foo = 5; inc(foo) => 6
- * inc(i) -> i+1; foo = 5; undef('foo'); inc(foo) => 1
- * inc(i) -> i+1; foo = 5; undef('inc'); undef('foo'); inc(foo) => Error: Function inc is not defined yet at pos 53
- * undef('pi') => bad idea - removes hidden variable holding the pi value
- * undef('true') => even worse idea, unbinds global true value, all references to true would now refer to the default 0
- *
- * vars(prefix)It returns all names of variables from local scope (if prefix does not start with 'global')
- * or global variables (otherwise).
- * Here is a larger example that uses combination of vars and var functions to
- * be used for object counting
- * /script run
- * $ count_blocks(ent) -> (
- * $ l(cx, cy, cz) = query(ent, 'pos');
- * $ scan(cx, cy, cz, 16, 16, 16, var('count_'+_) += 1);
- * $ for ( sort_key( vars('count_'), -var(_)),
- * $ print(str( '%s: %d', slice(_,6), var(_) ))
- * $ )
- * $ )
- *
- * /script run count_blocks(player())
- *
- *
- * Scarpet runs apps in isolation. The can share code via use of shared libraries, but each library that is imported - * to each app is specific to that app. Apps can store and fetch state from disk, but its restricted to specific locations - * meaning apps cannot interact via disk either. To facilitate communication for interappperability, scarpet hosts its own - * key-value storage that is shared between all apps currently running on the host, providing methods for getting - * an associated value with optional setting it if not present, and an operation of modifying a content of a system global - * value.
- *system_variable_get(key, default_value ?)Returns the variable from the system shared key-value storage keyed with a key value, optionally
- * if value is not present, and default expression is provided, sets a new value to be associated with that key
system_variable_set(key, new_value)Returns the variable from the system shared key-value storage keyed with a key value, and sets
- * a new mapping for the key