refactored scan to also take pos arguments.

docs/scarpet/api/BlockIterations.md

@@ -2,11 +2,15 @@
 
 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)`
+### `scan(cx, cy, cz, dx, dy, dz, px?, py?, pz?, expr)`, `scan(center, range, lower_range?, 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.
+Evaluates expression over area of blocks defined by its center `center = (cx, cy, cz)`, expanded in all directions 
+by `range = (dx, dy, dz)` blocks, or optionally in negative with `range` coords, and `upper_range` coords in 
+positive values.
+`center` can be defined either as a three coordinates, list of three coords, or block value.
+`range` and `lower_range` can have the same representations, just if its a block, it computes the distance to the center
+as range instead of taking the values as is.
+`expr` receives `_x, _y, _z` as coords of current analyzed block and `_`, which represents the block itself.
 
 Returns number of successful evaluations of `expr` (with `true` boolean result) unless called in void context, 
 which would cause the expression not be evaluated for their boolean value.

src/main/java/carpet/script/CarpetExpression.java

@@ -21,7 +21,6 @@ import carpet.script.exception.ContinueStatement;
 import carpet.script.exception.ExitStatement;
 import carpet.script.exception.ExpressionException;
 import carpet.script.exception.InternalExpressionException;
-import carpet.script.utils.CarpetArgParser;
 import carpet.script.value.BlockValue;
 import carpet.script.value.EntityValue;
 import carpet.script.value.FunctionValue;
@@ -109,6 +108,7 @@ import net.minecraft.util.math.Direction;
 import net.minecraft.util.math.EulerAngle;
 import net.minecraft.util.math.BlockBox;
 import net.minecraft.util.math.Vec3d;
+import net.minecraft.util.math.Vec3i;
 import net.minecraft.util.registry.Registry;
 import net.minecraft.world.poi.PointOfInterest;
 import net.minecraft.world.poi.PointOfInterestStorage;
@@ -1947,30 +1947,58 @@ public class CarpetExpression
     {
         this.expr.addLazyFunction("scan", -1, (c, t, lv) ->
         {
-            int lvsise = lv.size();
-            if (lvsise != 7 && lvsise != 10)
-                throw new InternalExpressionException("'scan' takes 2, or 3 triples of coords, and the expression");
-            int cx = (int) NumericValue.asNumber(lv.get(0).evalValue(c)).getLong();
-            int cy = (int) NumericValue.asNumber(lv.get(1).evalValue(c)).getLong();
-            int cz = (int) NumericValue.asNumber(lv.get(2).evalValue(c)).getLong();
-            int xrange = (int) NumericValue.asNumber(lv.get(3).evalValue(c)).getLong();
-            int yrange = (int) NumericValue.asNumber(lv.get(4).evalValue(c)).getLong();
-            int zrange = (int) NumericValue.asNumber(lv.get(5).evalValue(c)).getLong();
-            int xprange = xrange;
-            int yprange = yrange;
-            int zprange = zrange;
-            LazyValue expr;
-            if (lvsise == 7)
+            CarpetContext cc = (CarpetContext)c;
+            BlockArgument centerLocator = BlockArgument.findIn(cc, lv, 0);
+            Vector3Argument rangeLocator = Vector3Argument.findIn(cc, lv, centerLocator.offset);
+            BlockPos center = centerLocator.block.getPos();
+            Vec3i range;
+
+            if (rangeLocator.fromBlock)
             {
-                expr = lv.get(6);
+                range = new Vec3i(
+                        abs(rangeLocator.vec.x - center.getX()),
+                        abs(rangeLocator.vec.y - center.getY()),
+                        abs(rangeLocator.vec.z - center.getZ())
+                );
+                //if (lv.size() > rangeLocator.offset+1) throw new InternalExpressionException("'scan' takes two block positions, and the expression")
             }
             else
             {
-                xprange = (int) NumericValue.asNumber(lv.get(6).evalValue(c)).getLong();
-                yprange = (int) NumericValue.asNumber(lv.get(7).evalValue(c)).getLong();
-                zprange = (int) NumericValue.asNumber(lv.get(8).evalValue(c)).getLong();
-                expr = lv.get(9);
+                range = new Vec3i(abs(rangeLocator.vec.x), abs(rangeLocator.vec.y), abs(rangeLocator.vec.z));
             }
+            Vec3i upperRange = range;
+            if (lv.size() > rangeLocator.offset+1) // +1 cause we still need the expression
+            {
+                rangeLocator = Vector3Argument.findIn(cc, lv, rangeLocator.offset);
+                if (rangeLocator.fromBlock)
+                {
+                    upperRange = new Vec3i(
+                            abs(rangeLocator.vec.x - center.getX()),
+                            abs(rangeLocator.vec.y - center.getY()),
+                            abs(rangeLocator.vec.z - center.getZ())
+                    );
+                    //if (lv.size() > rangeLocator.offset+1) throw new InternalExpressionException("'scan' takes two block positions, and the expression")
+                }
+                else
+                {
+                    upperRange = new Vec3i(abs(rangeLocator.vec.x), abs(rangeLocator.vec.y), abs(rangeLocator.vec.z));
+                }
+            }
+            if (lv.size() != rangeLocator.offset+1)
+            {
+                throw new InternalExpressionException("'scan' takes two, or three block positions, and an expression: "+lv.size()+" "+rangeLocator.offset);
+            }
+            LazyValue expr = lv.get(rangeLocator.offset);
+
+            int cx = center.getX();
+            int cy = center.getY();
+            int cz = center.getZ();
+            int xrange = range.getX();
+            int yrange = range.getY();
+            int zrange = range.getZ();
+            int xprange = upperRange.getX();
+            int yprange = upperRange.getY();
+            int zprange = upperRange.getZ();
 
             //saving outer scope
             LazyValue _x = c.getVariable("_x");

src/main/java/carpet/script/argument/BlockArgument.java

@@ -77,7 +77,7 @@ public class BlockArgument extends Argument
         }
         catch (IndexOutOfBoundsException e)
         {
-            throw new InternalExpressionException("Block should be defined either by three coordinates, a block value, or a proper string");
+            throw handleError(optional, acceptString);
         }
     }
 
@@ -127,7 +127,18 @@ public class BlockArgument extends Argument
         }
         catch (IndexOutOfBoundsException e)
         {
-            throw new InternalExpressionException("Block should be defined either by three coordinates, a block value, or a proper string");
+            throw handleError(optional, acceptString);
         }
     }
+
+    private static InternalExpressionException handleError(boolean optional, boolean acceptString)
+    {
+        String message = "Block-type argument should be defined either by three coordinates (a triple or by three arguments), or a block value";
+        if (acceptString)
+            message+=", or a string with block description";
+        if (optional)
+            message+=", or null";
+        return new InternalExpressionException(message);
+    }
+
 }

src/main/java/carpet/script/argument/Vector3Argument.java

@@ -87,7 +87,7 @@ public class Vector3Argument extends Argument
         }
         catch (IndexOutOfBoundsException e)
         {
-            throw new InternalExpressionException("Position should be defined either by three coordinates, or a block value");
+            throw new InternalExpressionException("Position argument should be defined either by three coordinates (a triple or by three arguments), or a positioned block value");
         }
     }
 }

src/main/java/carpet/script/utils/CarpetArgParser.java

@@ -1,6 +0,0 @@
-package carpet.script.utils;
-
-
-public class CarpetArgParser
-{
-}