modules and imports

src/main/java/carpet/commands/ScriptCommand.java

@@ -37,6 +37,7 @@ import java.util.Locale;
 import java.util.concurrent.CompletableFuture;
 import java.util.function.Predicate;
 import java.util.function.Supplier;
+import java.util.stream.Collectors;
 
 import static net.minecraft.server.command.CommandManager.argument;
 import static net.minecraft.server.command.CommandManager.literal;
@@ -78,7 +79,7 @@ public class ScriptCommand
                 executes( (cc) -> { CarpetServer.scriptServer.stopAll = false; return 1;});
         LiteralArgumentBuilder<ServerCommandSource> l = literal("run").
                 requires((player) -> player.hasPermissionLevel(2)).
-                then(argument("expr", StringArgumentType.greedyString()).suggests((cc, bb) -> suggestCode(cc, bb)).
+                then(argument("expr", StringArgumentType.greedyString()).suggests(ScriptCommand::suggestCode).
                         executes((cc) -> compute(
                                 cc,
                                 StringArgumentType.getString(cc, "expr"))));
@@ -141,7 +142,7 @@ public class ScriptCommand
                         then(argument("from", BlockPosArgumentType.blockPos()).
                                 then(argument("to", BlockPosArgumentType.blockPos()).
                                         then(argument("expr", StringArgumentType.greedyString()).
-                                                suggests((cc, bb) -> suggestCode(cc, bb)).
+                                                suggests(ScriptCommand::suggestCode).
                                                 executes( (cc) -> scriptScan(
                                                         cc,
                                                         BlockPosArgumentType.getBlockPos(cc, "origin"),
@@ -288,7 +289,7 @@ public class ScriptCommand
     private static Collection<String> suggestFunctionCalls(CommandContext<ServerCommandSource> c)
     {
         CarpetScriptHost host = getHost(c);
-        return host.getPublicFunctions();
+        return host.globaFunctionNames(host.myCode, s ->  !s.startsWith("_")).sorted().collect(Collectors.toList());
     }
     private static int listEvents(ServerCommandSource source)
     {
@@ -314,9 +315,8 @@ public class ScriptCommand
         ServerCommandSource source = context.getSource();
 
         Messenger.m(source, "lb Stored functions"+((host == CarpetServer.scriptServer.globalHost)?":":" in "+host.getName()+":"));
-        for (String fname : host.getAvailableFunctions(all))
+        host.globaFunctionNames(host.myCode, (str) -> all || !str.startsWith("__")).sorted().forEach( (s) -> {
-        {
+            FunctionValue fun = host.getFunction(s);
-            FunctionValue fun = host.globalFunctions.get(fname);
             Expression expr = fun.getExpression();
             Tokenizer.Token tok = fun.getToken();
             List<String> snippet = ExpressionInspector.Expression_getExpressionSnippet(tok, expr);
@@ -326,16 +326,13 @@ public class ScriptCommand
                 Messenger.m(source, "w "+snippetLine);
             }
             Messenger.m(source, "gi ----------------");
-        }
+        });
         //Messenger.m(source, "w "+code);
         Messenger.m(source, "w  ");
         Messenger.m(source, "lb Global variables"+((host == CarpetServer.scriptServer.globalHost)?":":" in "+host.getName()+":"));
-
+        host.globaVariableNames(host.myCode, (s) -> s.startsWith("global_")).sorted().forEach( (s) -> {
-        for (String vname : host.globalVariables.keySet())
+            Messenger.m(source, "wb "+s+": ", "w "+ host.getGlobalVariable(s).evalValue(null).getPrettyString());
-        {
+        });
-            if (!vname.startsWith("global")) continue;
-            Messenger.m(source, "wb "+vname+": ", "w "+ host.globalVariables.get(vname).evalValue(null).getPrettyString());
-        }
         return 1;
     }
 
@@ -402,7 +399,7 @@ public class ScriptCommand
         ServerCommandSource source = context.getSource();
         CarpetScriptHost host = getHost(context);
         handleCall(source, host, () -> {
-            CarpetExpression ex = new CarpetExpression(expr, source, new BlockPos(0, 0, 0));
+            CarpetExpression ex = new CarpetExpression(host.myCode, expr, source, new BlockPos(0, 0, 0));
             return ex.scriptRunCommand(host, new BlockPos(source.getPosition()));
         });
         return 1;
@@ -413,7 +410,8 @@ public class ScriptCommand
         ServerCommandSource source = context.getSource();
         CarpetScriptHost host = getHost(context);
         MutableIntBoundingBox area = new MutableIntBoundingBox(a, b);
-        CarpetExpression cexpr = new CarpetExpression(expr, source, origin);
+        CarpetExpression cexpr = new CarpetExpression(host.myCode, expr, source, origin);
+
         int int_1 = area.getBlockCountX() * area.getBlockCountY() * area.getBlockCountZ();
         if (int_1 > CarpetSettings.fillLimit)
         {
@@ -463,7 +461,7 @@ public class ScriptCommand
         ServerCommandSource source = context.getSource();
         CarpetScriptHost host = getHost(context);
         MutableIntBoundingBox area = new MutableIntBoundingBox(a, b);
-        CarpetExpression cexpr = new CarpetExpression(expr, source, origin);
+        CarpetExpression cexpr = new CarpetExpression(host.myCode, expr, source, origin);
         int int_1 = area.getBlockCountX() * area.getBlockCountY() * area.getBlockCountZ();
         if (int_1 > CarpetSettings.fillLimit)
         {

src/main/java/carpet/script/CarpetContext.java

@@ -1,5 +1,6 @@
 package carpet.script;
 
+import carpet.script.value.Value;
 import net.minecraft.server.command.ServerCommandSource;
 import net.minecraft.util.math.BlockPos;
 
@@ -15,9 +16,17 @@ public class CarpetContext extends Context
     }
 
     @Override
-    public Context recreate()
+    public Context duplicate()
     {
         return new CarpetContext(this.host, this.s, this.origin);
     }
 
+    @Override
+    protected void initialize()
+    {
+        super.initialize();
+        variables.put("_x", (c, t) -> Value.ZERO);
+        variables.put("_y", (c, t) -> Value.ZERO);
+        variables.put("_z", (c, t) -> Value.ZERO);
+    }
 }

src/main/java/carpet/script/CarpetEventServer.java

@@ -130,7 +130,7 @@ public class CarpetEventServer
                 // impossible call to add
                 return false;
             }
-            FunctionValue udf = host.globalFunctions.get(funName);
+            FunctionValue udf = host.getFunction(funName);
             if (udf == null || udf.getArguments().size() != reqArgs)
             {
                 // call won't match arguments

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

@@ -7,6 +7,7 @@ import carpet.helpers.FeatureGenerator;
 import carpet.mixins.ChunkTicketManager_scarpetMixin;
 import carpet.mixins.ServerChunkManager_scarpetMixin;
 import carpet.script.Fluff.TriFunction;
+import carpet.script.bundled.Module;
 import carpet.script.exception.CarpetExpressionException;
 import carpet.script.exception.ExitStatement;
 import carpet.script.exception.ExpressionException;
@@ -2135,9 +2136,7 @@ public class CarpetExpression
             else if (!(functionValue instanceof FunctionValue))
             {
                 String name = functionValue.getString();
-                functionValue = c.host.globalFunctions.get(name);
+                functionValue = c.host.getAssertFunction(this.expr.module, name);
-                if (functionValue == null)
-                    throw new InternalExpressionException("Function "+name+" is not defined yet");
             }
             FunctionValue function = (FunctionValue)functionValue;
             List<Value> args = null;
@@ -3194,9 +3193,7 @@ public class CarpetExpression
             if (!(functionValue instanceof FunctionValue))
             {
                 String name = functionValue.getString();
-                functionValue = c.host.globalFunctions.get(name);
+                functionValue = c.host.getAssertFunction(this.expr.module, name);
-                if (functionValue == null)
-                    throw new InternalExpressionException("Function "+name+" is not defined yet");
             }
             FunctionValue function = (FunctionValue)functionValue;
 
@@ -3298,11 +3295,13 @@ public class CarpetExpression
      * @param source source
      * @param origin origin
      */
-    public CarpetExpression(String expression, ServerCommandSource source, BlockPos origin)
+    public CarpetExpression(Module module, String expression, ServerCommandSource source, BlockPos origin)
     {
         this.origin = origin;
         this.source = source;
         this.expr = new Expression(expression);
+        this.expr.asAModule(module);
+
 
         API_BlockManipulation();
         API_EntityManipulation();

src/main/java/carpet/script/CarpetScriptHost.java

@@ -1,7 +1,7 @@
 package carpet.script;
 
 import carpet.CarpetServer;
-import carpet.script.bundled.ModuleInterface;
+import carpet.script.bundled.Module;
 import carpet.script.exception.CarpetExpressionException;
 import carpet.script.exception.ExpressionException;
 import carpet.script.exception.InternalExpressionException;
@@ -36,7 +36,7 @@ public class CarpetScriptHost extends ScriptHost
     private Tag globalState;
     private int saveTimeout;
 
-    private CarpetScriptHost(CarpetScriptServer server, ModuleInterface code, boolean perUser, ScriptHost parent)
+    private CarpetScriptHost(CarpetScriptServer server, Module code, boolean perUser, ScriptHost parent)
     {
         super(code, perUser, parent);
         this.saveTimeout = 0;
@@ -45,12 +45,9 @@ public class CarpetScriptHost extends ScriptHost
             globalState = loadState();
     }
 
-    public static CarpetScriptHost create(CarpetScriptServer scriptServer, ModuleInterface module, boolean perPlayer, ServerCommandSource source)
+    public static CarpetScriptHost create(CarpetScriptServer scriptServer, Module module, boolean perPlayer, ServerCommandSource source)
     {
         CarpetScriptHost host = new CarpetScriptHost(scriptServer, module, perPlayer, null );
-        host.globalVariables.put("_x", (c, t) -> Value.ZERO);
-        host.globalVariables.put("_y", (c, t) -> Value.ZERO);
-        host.globalVariables.put("_z", (c, t) -> Value.ZERO);
         // parse code and convert to expression
         if (module != null)
         {
@@ -63,8 +60,8 @@ public class CarpetScriptHost extends ScriptHost
                     return null;
                 }
                 host.setChatErrorSnooper(source);
-                CarpetExpression ex = new CarpetExpression(code, source, new BlockPos(0, 0, 0));
+                CarpetExpression ex = new CarpetExpression(host.myCode, code, source, new BlockPos(0, 0, 0));
-                ex.getExpr().asAModule(module);
+                ex.getExpr().asATextSource();
                 ex.scriptRunCommand(host, new BlockPos(source.getPosition()));
             }
             catch (CarpetExpressionException e)
@@ -85,11 +82,11 @@ public class CarpetScriptHost extends ScriptHost
     }
 
     @Override
-    public void addUserDefinedFunction(String funName, FunctionValue function)
+    public void addUserDefinedFunction(Module module, String funName, FunctionValue function)
     {
-        super.addUserDefinedFunction(funName, function);
+        super.addUserDefinedFunction(module, funName, function);
         // mcarpet
-        if (funName.startsWith("__on_"))
+        if (funName.startsWith("__on_")) // here we can make a determination if we want to only accept events from main module.
         {
             // this is nasty, we have the host and function, yet we add it via names, but hey - works for now
             String event = funName.replaceFirst("__on_","");
@@ -99,35 +96,27 @@ public class CarpetScriptHost extends ScriptHost
     }
 
     @Override
-    protected ModuleInterface getModuleByName(String name)
+    protected Module getModuleByName(String name)
     {
-        ModuleInterface module = scriptServer.getModule(name);
+        Module module = scriptServer.getModule(name);
         if (module == null || module.getCode() == null)
             throw new InternalExpressionException("Unable to locate package: "+name);
         return module;
     }
 
     @Override
-    protected boolean runModuleCode(Context c, ModuleInterface module)
+    protected void runModuleCode(Context c, Module module)
     {
         CarpetContext cc = (CarpetContext)c;
-        try
+        CarpetExpression ex = new CarpetExpression(module, module.getCode(), cc.s, cc.origin);
-        {
+        ex.getExpr().asATextSource();
-            CarpetExpression ex = new CarpetExpression(module.getCode(), cc.s, cc.origin);
+        ex.scriptRunCommand(this, cc.origin);
-            ex.getExpr().asAModule(module);
-            ex.scriptRunCommand(this, cc.origin);
-        }
-        catch (CarpetExpressionException e) // hopefully that error got reported already
-        {
-            throw new InternalExpressionException(e.getMessage());
-        }
-        return true;
     }
 
     @Override
-    public void delFunction(String funName)
+    public void delFunction(Module module, String funName)
     {
-        super.delFunction(funName);
+        super.delFunction(module, funName);
         // mcarpet
         if (funName.startsWith("__on_"))
         {
@@ -157,7 +146,7 @@ public class CarpetScriptHost extends ScriptHost
     {
         if (CarpetServer.scriptServer.stopAll)
             return "SCARPET PAUSED";
-        FunctionValue function = globalFunctions.get(call);
+        FunctionValue function = getFunction(call);
         if (function == null)
             return "UNDEFINED";
         List<LazyValue> argv = new ArrayList<>();
@@ -170,9 +159,10 @@ public class CarpetScriptHost extends ScriptHost
             switch (tok.type)
             {
                 case VARIABLE:
-                    if (globalVariables.containsKey(tok.surface.toLowerCase(Locale.ROOT)))
+                    LazyValue var = getGlobalVariable(tok.surface.toLowerCase(Locale.ROOT));
+                    if (var != null)
                     {
-                        argv.add(globalVariables.get(tok.surface.toLowerCase(Locale.ROOT)));
+                        argv.add(var);
                         break;
                     }
                 case STRINGPARAM:
@@ -238,7 +228,7 @@ public class CarpetScriptHost extends ScriptHost
         {
             // TODO: this is just for now - invoke would be able to invoke other hosts scripts
             Context context = new CarpetContext(this, source, BlockPos.ORIGIN);
-            return Expression.evalValue(
+            return function.getExpression().evalValue(
                     () -> function.lazyEval(context, Context.VOID, function.getExpression(), function.getToken(), argv),
                     context,
                     Context.VOID
@@ -262,7 +252,7 @@ public class CarpetScriptHost extends ScriptHost
         {
             // TODO: this is just for now - invoke would be able to invoke other hosts scripts
             Context context = new CarpetContext(this, source, pos);
-            return Expression.evalValue(
+            return fun.getExpression().evalValue(
                     () -> fun.lazyEval(context, Context.VOID, fun.getExpression(), fun.getToken(), argv),
                     context,
                     Context.VOID);
@@ -281,7 +271,7 @@ public class CarpetScriptHost extends ScriptHost
         if (this.saveTimeout > 0)
             dumpState();
 
-        FunctionValue closing = globalFunctions.get("__on_close");
+        FunctionValue closing = getFunction("__on_close");
         if (closing != null)
         {
             try
@@ -294,7 +284,7 @@ public class CarpetScriptHost extends ScriptHost
         }
         userHosts.forEach((key, value) ->
         {
-            FunctionValue userClosing = value.globalFunctions.get("__on_close");
+            FunctionValue userClosing = value.getFunction("__on_close");
             if (userClosing != null)
             {
                 ServerPlayerEntity player = CarpetServer.minecraft_server.getPlayerManager().getPlayer(key);
@@ -373,7 +363,7 @@ public class CarpetScriptHost extends ScriptHost
 
     public void setChatErrorSnooper(ServerCommandSource source)
     {
-        errorSnooper = (expr, token, message) ->
+        errorSnooper = (expr, /*Nullable*/ token, message) ->
         {
             try
             {
@@ -383,29 +373,43 @@ public class CarpetScriptHost extends ScriptHost
             {
                 return null;
             }
-            String[] lines = expr.getCodeString().split("\n");
+
             String shebang = message;
-            if (lines.length > 1)
+            if (expr.module != null)
             {
-                shebang += " at line "+(token.lineno+1)+", pos "+(token.linepos+1);
+                shebang += " in " + expr.module.getName() + "";
             }
-            else {
+            else
-                shebang += " at pos "+(token.pos+1);
-            }
-            if (expr.getName() != null)
             {
-                shebang += " in "+expr.getName()+"";
+                shebang += " in system chat";
             }
-            Messenger.m(source, "r "+shebang);
+            if (token != null)
-            if (lines.length > 1 && token.lineno > 0)
             {
-                Messenger.m(source, "l "+lines[token.lineno-1]);
+                String[] lines = expr.getCodeString().split("\n");
+
+                if (lines.length > 1)
+                {
+                    shebang += " at line " + (token.lineno + 1) + ", pos " + (token.linepos + 1);
+                }
+                else
+                {
+                    shebang += " at pos " + (token.pos + 1);
+                }
+                Messenger.m(source, "r " + shebang);
+                if (lines.length > 1 && token.lineno > 0)
+                {
+                    Messenger.m(source, "l " + lines[token.lineno - 1]);
+                }
+                Messenger.m(source, "l " + lines[token.lineno].substring(0, token.linepos), "r  HERE>> ", "l " +
+                        lines[token.lineno].substring(token.linepos));
+                if (lines.length > 1 && token.lineno < lines.length - 1)
+                {
+                    Messenger.m(source, "l " + lines[token.lineno + 1]);
+                }
             }
-            Messenger.m(source, "l "+lines[token.lineno].substring(0, token.linepos), "r  HERE>> ", "l "+
+            else
-                    lines[token.lineno].substring(token.linepos));
-            if (lines.length > 1 && token.lineno < lines.length-1)
             {
-                Messenger.m(source, "l "+lines[token.lineno+1]);
+                Messenger.m(source, "r " + shebang);
             }
             return new ArrayList<>();
         };

src/main/java/carpet/script/CarpetScriptServer.java

@@ -7,7 +7,7 @@ import carpet.script.value.StringValue;
 import carpet.CarpetSettings;
 import carpet.CarpetServer;
 import carpet.script.bundled.FileModule;
-import carpet.script.bundled.ModuleInterface;
+import carpet.script.bundled.Module;
 import carpet.script.exception.InvalidCallbackException;
 import carpet.script.value.Value;
 import carpet.utils.Messenger;
@@ -40,7 +40,7 @@ public class CarpetScriptServer
     private final Set<String> holyMoly;
     public final CarpetEventServer events;
 
-    private static final List<ModuleInterface> bundledModuleData = new ArrayList<ModuleInterface>(){{
+    private static final List<Module> bundledModuleData = new ArrayList<Module>(){{
         add(new BundledModule("camera"));
         add(new BundledModule("event_test"));
         add(new BundledModule("stats_test"));
@@ -69,7 +69,7 @@ public class CarpetScriptServer
 
     }
 
-    public ModuleInterface getModule(String name)
+    public Module getModule(String name)
     {
         File folder = CarpetServer.minecraft_server.getLevelStorage().resolveFile(
                 CarpetServer.minecraft_server.getLevelName(), "scripts");
@@ -82,7 +82,7 @@ public class CarpetScriptServer
                     return new FileModule(script);
                 }
             }
-        for (ModuleInterface moduleData : bundledModuleData)
+        for (Module moduleData : bundledModuleData)
         {
             if (moduleData.getName().equalsIgnoreCase(name))
             {
@@ -97,7 +97,7 @@ public class CarpetScriptServer
         List<String> moduleNames = new ArrayList<>();
         if (includeBuiltIns)
         {
-            for (ModuleInterface mi : bundledModuleData)
+            for (Module mi : bundledModuleData)
             {
                 moduleNames.add(mi.getName());
             }
@@ -129,7 +129,7 @@ public class CarpetScriptServer
     {
         //TODO add per player modules to support player actions better on a server
         name = name.toLowerCase(Locale.ROOT);
-        ModuleInterface module = getModule(name);
+        Module module = getModule(name);
         if (module == null)
         {
             Messenger.m(source, "r Failed to add "+name+" app");
@@ -170,13 +170,13 @@ public class CarpetScriptServer
     private boolean addConfig(ServerCommandSource source, String hostName)
     {
         CarpetScriptHost host = modules.get(hostName);
-        if (host == null || !host.globalFunctions.containsKey("__config"))
+        if (host == null || host.getFunction("__config") == null)
         {
             return false;
         }
         try
         {
-            Value ret = host.callUDF(BlockPos.ORIGIN, source, host.globalFunctions.get("__config"), Collections.emptyList());
+            Value ret = host.callUDF(BlockPos.ORIGIN, source, host.getFunction("__config"), Collections.emptyList());
             if (!(ret instanceof MapValue)) return false;
             Map<Value, Value> config = ((MapValue) ret).getMap();
             host.setPerPlayer(config.getOrDefault(new StringValue("scope"), new StringValue("player")).getString().equalsIgnoreCase("player"));
@@ -195,7 +195,7 @@ public class CarpetScriptServer
         {
             return;
         }
-        if (!host.globalFunctions.containsKey("__command"))
+        if (host.getFunction("__command") == null)
         {
             Messenger.m(source, "gi "+hostName+" app loaded.");
             return;
@@ -217,11 +217,11 @@ public class CarpetScriptServer
                     return 1;
                 });
 
-        for (String function : host.getPublicFunctions())
+        for (String function : host.globaFunctionNames(host.myCode, s ->  !s.startsWith("_")).sorted().collect(Collectors.toList()))
         {
             command = command.
                     then(literal(function).
-                            requires((player) -> modules.containsKey(hostName) && modules.get(hostName).getPublicFunctions().contains(function)).
+                            requires((player) -> modules.containsKey(hostName) && modules.get(hostName).getFunction(function) != null).
                             executes( (c) -> {
                                 String response = modules.get(hostName).retrieveForExecution(c.getSource()).
                                         call(c.getSource(), function,null,"");

src/main/java/carpet/script/Context.java

@@ -1,5 +1,7 @@
 package carpet.script;
 
+import carpet.script.value.Value;
+
 import java.util.HashMap;
 import java.util.Map;
 import java.util.Set;
@@ -26,38 +28,26 @@ public class Context
         this.host = host;
     }
 
-
     LazyValue getVariable(String name)
     {
-        if (variables.containsKey(name))
+        return variables.get(name);
-        {
-            return variables.get(name);
-        }
-        return host.globalVariables.get(name);
     }
 
     public void setVariable(String name, LazyValue lv)
     {
-        if (name.startsWith("global_"))
-        {
-            host.globalVariables.put(name, lv);
-            return;
-        }
         variables.put(name, lv);
     }
 
-
-    boolean isAVariable(String name)
-    {
-        return variables.containsKey(name) || host.globalVariables.containsKey(name);
-    }
-
-
     void delVariable(String variable)
     {
         variables.remove(variable);
     }
 
+    public void removeVariablesMatching(String varname)
+    {
+        variables.entrySet().removeIf(e -> e.getKey().startsWith(varname));
+    }
+
     public Context with(String variable, LazyValue lv)
     {
         variables.put(variable, lv);
@@ -70,6 +60,21 @@ public class Context
     }
 
     public Context recreate()
+    {
+        Context ctx = duplicate();
+        ctx.initialize();
+        return ctx;
+    }
+
+    protected void initialize()
+    {
+        //special variables for second order functions so we don't need to check them all the time
+        variables.put("_", (c, t) -> Value.ZERO);
+        variables.put("_i", (c, t) -> Value.ZERO);
+        variables.put("_a", (c, t) -> Value.ZERO);
+    }
+
+    public Context duplicate()
     {
         return new Context(this.host);
     }

src/main/java/carpet/script/Expression.java

@@ -11,12 +11,13 @@ import carpet.script.Fluff.QuadFunction;
 import carpet.script.Fluff.QuinnFunction;
 import carpet.script.Fluff.SexFunction;
 import carpet.script.Fluff.TriFunction;
-import carpet.script.bundled.ModuleInterface;
+import carpet.script.bundled.Module;
 import carpet.script.exception.BreakStatement;
 import carpet.script.exception.ContinueStatement;
 import carpet.script.exception.ExitStatement;
 import carpet.script.exception.ExpressionException;
 import carpet.script.exception.InternalExpressionException;
+import carpet.script.exception.ResolvedException;
 import carpet.script.exception.ReturnStatement;
 import carpet.script.exception.ThrowStatement;
 import carpet.script.value.AbstractListValue;
@@ -332,7 +333,7 @@ import static java.lang.Math.min;
  * </p>
  */
 
-public class Expression implements Cloneable
+public class Expression
 {
     private static final Map<String, Integer> precedence = new HashMap<String,Integer>() {{
         put("attribute~:", 80);
@@ -366,21 +367,18 @@ public class Expression implements Cloneable
     private boolean allowNewlineSubstitutions = true;
     private boolean allowComments = false;
 
-    public ModuleInterface module = null;
+    public Module module = null;
 
-    void asAModule(ModuleInterface mi)
+    void asATextSource()
     {
         allowNewlineSubstitutions = false;
         allowComments = true;
-        module = mi;
     }
 
-    private String name;
+    void asAModule(Module mi)
-    String getName() {return name;}
-    Expression withName(String alias)
     {
-        name = alias;
+
-        return this;
+        module = mi;
     }
 
     /** Cached AST (Abstract Syntax Tree) (root) of the expression */
@@ -393,18 +391,6 @@ public class Expression implements Cloneable
     private final Map<String, ILazyFunction> functions = new  Object2ObjectOpenHashMap<>();
     Set<String> getFunctionNames() {return functions.keySet();}
 
-    @Override
-    protected Expression clone() throws CloneNotSupportedException
-    {
-        // very very shallow copy for global functions to grab the context for error msgs
-        Expression copy = (Expression) super.clone();
-        copy.expression = this.expression;
-        copy.name = this.name;
-        copy.module = this.module;
-        return copy;
-    }
-
-
     static List<String> getExpressionSnippet(Tokenizer.Token token, Expression expr)
     {
         String code = expr.getCodeString();
@@ -561,7 +547,7 @@ public class Expression implements Cloneable
             return new ExpressionException(c, e, token, exc.getMessage(), ((InternalExpressionException) exc).stack);
         if (exc instanceof ArithmeticException)
             return new ExpressionException(c, e, token, "Your math is wrong, "+exc.getMessage());
-        if (exc instanceof ExpressionException)
+        if (exc instanceof ResolvedException)
             return exc;
         // unexpected really - should be caught earlier and converted to InternalExpressionException
         exc.printStackTrace();
@@ -669,29 +655,29 @@ public class Expression implements Cloneable
             }
         });
     }
-    private FunctionValue addContextFunction(Context context, String name, Expression expr, Tokenizer.Token token, List<String> arguments, List<String> globals, LazyValue code)
+    private FunctionValue addContextFunction(Context context, String name, Expression expr, Tokenizer.Token token, List<String> arguments, List<String> outers, LazyValue code)
     {
         name = name.toLowerCase(Locale.ROOT);
         if (functions.containsKey(name))
             throw new ExpressionException(context, expr, token, "Function "+name+" would mask a built-in function");
         Map<String, LazyValue> contextValues = new HashMap<>();
-        for (String global : globals)
+        for (String outer : outers)
         {
-            LazyValue  lv = context.getVariable(global);
+            LazyValue  lv = context.getVariable(outer);
             if (lv == null)
             {
-                throw new InternalExpressionException("Variable "+global+" needs to be defined in outer scope to be used as outer parameter");
+                throw new InternalExpressionException("Variable "+outer+" needs to be defined in outer scope to be used as outer parameter, and cannot be global");
             }
             else
             {
-                contextValues.put(global, lv);
+                contextValues.put(outer, lv);
             }
         }
         if (contextValues.isEmpty()) contextValues = null;
 
         FunctionValue result =  new FunctionValue(expr, token, name, code, arguments, contextValues);
         // do not store lambda definitions
-        if (!name.equals("_")) context.host.addUserDefinedFunction(name, result);
+        if (!name.equals("_")) context.host.addUserDefinedFunction(module, name, result);
         return result;
     }
 
@@ -869,11 +855,13 @@ public class Expression implements Cloneable
     public void UserDefinedFunctionsAndControlFlow() // public just to get the javadoc right
     {
         // artificial construct to handle user defined functions and function definitions
-        addLazyFunction("import", 1, (c, t, lv) ->
+        addLazyFunction("import", -1, (c, t, lv) ->
         {
-            boolean success = c.host.importModule(c, lv.get(0).evalValue(c).getString());
+            if (lv.size() < 2) throw new InternalExpressionException("'import' needs at least a module name to import, and list of values to import");
-            Value ret = new NumericValue(success);
+            String moduleName = lv.get(0).evalValue(c).getString();
-            return (cc, tt) -> ret;
+            c.host.importModule(c, moduleName);
+            c.host.importNames(c, module, moduleName, lv.subList(1, lv.size()).stream().map((l) -> l.evalValue(c).getString()).collect(Collectors.toList()));
+            return (cc, tt) -> Value.NULL;
         });
 
         addLazyFunctionWithDelegation("call",-1, (c, t, expr, tok, lv) -> { // adjust based on c
@@ -886,9 +874,7 @@ public class Expression implements Cloneable
                 if (!(functionValue instanceof FunctionValue))
                 {
                     String name = functionValue.getString();
-                    functionValue = c.host.globalFunctions.get(name);
+                    functionValue = c.host.getAssertFunction(module, name);
-                    if (functionValue == null)
-                        throw new InternalExpressionException("Function "+name+" is not defined yet");
                 }
                 List<LazyValue> lvargs = new ArrayList<>(lv.size()-1);
                 for (int i=1; i< lv.size(); i++)
@@ -1255,7 +1241,7 @@ public class Expression implements Cloneable
                 {
                     String lname = li.next().getVariable();
                     Value vval = ri.next().reboundedTo(lname);
-                    c.setVariable(lname, (cc, tt) -> vval);
+                    setAnyVariable(c, lname, (cc, tt) -> vval);
                 }
                 return (cc, tt) -> Value.TRUE;
             }
@@ -1272,7 +1258,7 @@ public class Expression implements Cloneable
             String varname = v1.getVariable();
             Value copy = v2.reboundedTo(varname);
             LazyValue boundedLHS = (cc, tt) -> copy;
-            c.setVariable(varname, boundedLHS);
+            setAnyVariable(c, varname, boundedLHS);
             return boundedLHS;
         });
 
@@ -1294,7 +1280,7 @@ public class Expression implements Cloneable
                     Value lval = li.next();
                     String lname = lval.getVariable();
                     Value result = lval.add(ri.next()).bindTo(lname);
-                    c.setVariable(lname, (cc, tt) -> result);
+                    setAnyVariable(c, lname, (cc, tt) -> result);
                 }
                 return (cc, tt) -> Value.TRUE;
             }
@@ -1323,7 +1309,7 @@ public class Expression implements Cloneable
                 Value result = v1.add(v2).bindTo(varname);
                 boundedLHS = (cc, tt) -> result;
             }
-            c.setVariable(varname, boundedLHS);
+            setAnyVariable(c, varname, boundedLHS);
             return boundedLHS;
         });
 
@@ -1349,8 +1335,8 @@ public class Expression implements Cloneable
                     String rname = rval.getVariable();
                     lval.reboundedTo(rname);
                     rval.reboundedTo(lname);
-                    c.setVariable(lname, (cc, tt) -> rval);
+                    setAnyVariable(c, lname, (cc, tt) -> rval);
-                    c.setVariable(rname, (cc, tt) -> lval);
+                    setAnyVariable(c, rname, (cc, tt) -> lval);
                 }
                 return (cc, tt) -> Value.TRUE;
             }
@@ -1360,8 +1346,8 @@ public class Expression implements Cloneable
             String rvalvar = v2.getVariable();
             Value lval = v2.reboundedTo(lvalvar);
             Value rval = v1.reboundedTo(rvalvar);
-            c.setVariable(lvalvar, (cc, tt) -> lval);
+            setAnyVariable(c, lvalvar, (cc, tt) -> lval);
-            c.setVariable(rvalvar, (cc, tt) -> rval);
+            setAnyVariable(c, rvalvar, (cc, tt) -> rval);
             return (cc, tt) -> lval;
         });
 
@@ -2991,9 +2977,7 @@ public class Expression implements Cloneable
 
         addLazyFunction("var", 1, (c, t, lv) -> {
             String varname = lv.get(0).evalValue(c).getString();
-            if (!c.isAVariable(varname))
+            return getOrSetAnyVariable(c, varname);
-                c.setVariable(varname, (_c, _t ) -> Value.ZERO.reboundedTo(varname));
-            return c.getVariable(varname);
         });
 
         addLazyFunction("undef", 1, (c, t, lv) ->
@@ -3001,7 +2985,7 @@ public class Expression implements Cloneable
             Value remove = lv.get(0).evalValue(c);
             if (remove instanceof FunctionValue)
             {
-                c.host.delFunction(remove.getString());
+                c.host.delFunction(module, remove.getString());
                 return (cc, tt) -> Value.NULL;
             }
             String varname = remove.getString();
@@ -3010,33 +2994,24 @@ public class Expression implements Cloneable
                 varname = varname.replaceAll("\\*+$", "");
             if (isPrefix)
             {
-                for (String key: c.host.globalFunctions.keySet())
+                c.host.delFunctionWithPrefix(module, varname);
-                {
-                    if (key.startsWith(varname)) c.host.delFunction(key);
-                }
                 if (varname.startsWith("global_"))
                 {
-                    for (String key : c.host.globalVariables.keySet())
+                    c.host.delGlobalVariableWithPrefix(module, varname);
-                    {
-                        if (key.startsWith(varname)) c.host.delGlobalVariable(key);
-                    }
                 }
-                if (!varname.startsWith("_"))
+                else if (!varname.startsWith("_"))
                 {
-                    for (String key : c.variables.keySet())
+                    c.removeVariablesMatching(varname);
-                    {
-                        if (key.startsWith(varname)) c.delVariable(key);
-                    }
                 }
             }
             else
             {
-                c.host.delFunction(varname);
+                c.host.delFunction(module, varname);
                 if (varname.startsWith("global_"))
                 {
-                    c.host.delGlobalVariable(varname);
+                    c.host.delGlobalVariable(module, varname);
                 }
-                if (!varname.startsWith("_"))
+                else if (!varname.startsWith("_"))
                 {
                     c.delVariable(varname);
                 }
@@ -3044,25 +3019,17 @@ public class Expression implements Cloneable
             return (cc, tt) -> Value.NULL;
         });
 
-
+        //deprecate
         addLazyFunction("vars", 1, (c, t, lv) -> {
             String prefix = lv.get(0).evalValue(c).getString();
             List<Value> values = new ArrayList<>();
             if (prefix.startsWith("global"))
             {
-                for (String k: c.host.globalVariables.keySet())
+                c.host.globaVariableNames(module, (s) -> s.startsWith(prefix)).forEach(s -> values.add(new StringValue(s)));
-                {
-                    if (k.startsWith(prefix))
-                        values.add(new StringValue(k));
-                }
             }
             else
             {
-                for (String k: c.getAllVariableNames())
+                c.getAllVariableNames().stream().filter(s -> s.startsWith(prefix)).forEach(s -> values.add(new StringValue(s)));
-                {
-                    if (k.startsWith(prefix))
-                        values.add(new StringValue(k));
-                }
             }
             Value retval = ListValue.wrap(values);
             return (cc, tt) -> retval;
@@ -3075,9 +3042,7 @@ public class Expression implements Cloneable
             if (!(funcDesc instanceof FunctionValue))
             {
                 String name = funcDesc.getString();
-                funcDesc = c.host.globalFunctions.get(name);
+                funcDesc = c.host.getAssertFunction(module, name);
-                if (funcDesc == null)
-                    throw new InternalExpressionException("Function "+name+" is not defined yet");
             }
             FunctionValue fun = (FunctionValue)funcDesc;
             int extraargs = lv.size() - fun.getArguments().size();
@@ -3127,6 +3092,33 @@ public class Expression implements Cloneable
 
     }
 
+    private void setAnyVariable(Context c, String name, LazyValue lv)
+    {
+        if (name.startsWith("global_"))
+        {
+            c.host.setGlobalVariable(module, name, lv);
+        }
+        else
+        {
+            c.setVariable(name, lv);
+        }
+    }
+
+    private LazyValue getOrSetAnyVariable(Context c, String name)
+    {
+        LazyValue var = null;
+        if (!name.startsWith("global_"))
+        {
+            var = c.getVariable(name);
+            if (var != null) return var;
+        }
+        var = c.host.getGlobalVariable(module, name);
+        if (var != null) return var;
+        var = (_c, _t ) -> Value.ZERO.reboundedTo(name);
+        setAnyVariable(c, name, var);
+        return var;
+    }
+
     static final Expression none = new Expression("null");
     /**
      * @param expression .
@@ -3143,6 +3135,7 @@ public class Expression implements Cloneable
         BasicDataStructures();
     }
 
+
     private List<Tokenizer.Token> shuntingYard(Context c)
     {
         List<Tokenizer.Token> outputQueue = new ArrayList<>();
@@ -3267,7 +3260,7 @@ public class Expression implements Cloneable
                     }
                     if (stack.isEmpty())
                     {
-                        throw new ExpressionException(c, "Mismatched parentheses");
+                        throw new ExpressionException(c, this, "Mismatched parentheses");
                     }
                     stack.pop();
                     if (!stack.isEmpty() && stack.peek().type == Tokenizer.Token.TokenType.FUNCTION)
@@ -3325,7 +3318,7 @@ public class Expression implements Cloneable
         return evalValue(() -> ast, c, expectedType);
     }
 
-    static Value evalValue(Supplier<LazyValue> exprProvider, Context c, Integer expectedType)
+    Value evalValue(Supplier<LazyValue> exprProvider, Context c, Integer expectedType)
     {
         try
         {
@@ -3333,7 +3326,7 @@ public class Expression implements Cloneable
         }
         catch (ContinueStatement | BreakStatement | ReturnStatement exc)
         {
-            throw new ExpressionException(c, "Control flow functions, like continue, break, or return, should only be used in loops and functions respectively.");
+            throw new ExpressionException(c, this, "Control flow functions, like continue, break, or return, should only be used in loops and functions respectively.");
         }
         catch (ExitStatement exit)
         {
@@ -3341,15 +3334,15 @@ public class Expression implements Cloneable
         }
         catch (StackOverflowError ignored)
         {
-            throw new ExpressionException(c, "Your thoughts are too deep");
+            throw new ExpressionException(c, this, "Your thoughts are too deep");
         }
         catch (InternalExpressionException exc)
         {
-            throw new ExpressionException(c, "Your expression result is incorrect:"+exc.getMessage());
+            throw new ExpressionException(c, this, "Your expression result is incorrect:"+exc.getMessage());
         }
         catch (ArithmeticException exc)
         {
-            throw new ExpressionException(c, "The final result is incorrect, "+exc.getMessage());
+            throw new ExpressionException(c, this, "The final result is incorrect, "+exc.getMessage());
         }
     }
 
@@ -3376,15 +3369,7 @@ public class Expression implements Cloneable
                     stack.push(result);
                     break;
                 case VARIABLE:
-                    stack.push((c, t) ->
+                    stack.push((c, t) -> getOrSetAnyVariable(c, token.surface).evalValue(c));
-                    {
-                        if (!c.isAVariable(token.surface)) // new variable
-                        {
-                            c.setVariable(token.surface, (cc, tt ) -> Value.ZERO.reboundedTo(token.surface));
-                        }
-                        LazyValue lazyVariable = c.getVariable(token.surface);
-                        return lazyVariable.evalValue(c);
-                    });
                     break;
                 case FUNCTION:
                     String name = token.surface.toLowerCase(Locale.ROOT);
@@ -3507,15 +3492,15 @@ public class Expression implements Cloneable
 
         if (stack.size() > 1)
         {
-            throw new ExpressionException(c, "Too many unhandled function parameter lists");
+            throw new ExpressionException(c, this, "Too many unhandled function parameter lists");
         }
         else if (stack.peek() > 1)
         {
-            throw new ExpressionException(c, "Too many numbers or variables");
+            throw new ExpressionException(c, this, "Too many numbers or variables");
         }
         else if (stack.peek() < 1)
         {
-            throw new ExpressionException(c, "Empty expression");
+            throw new ExpressionException(c, this, "Empty expression");
         }
     }
 

src/main/java/carpet/script/ExpressionInspector.java

@@ -1,6 +1,5 @@
 package carpet.script;
 
-import carpet.script.exception.ExpressionException;
 import org.apache.commons.lang3.StringUtils;
 
 import java.util.Collections;
@@ -21,31 +20,17 @@ public class ExpressionInspector
         return Expression.getExpressionSnippet(token, expr);
     }
 
-    public static String Expression_getName(Expression e)
+    public static String Expression_getModuleName(Expression e)
     {
-        return e.getName();
+        return e.module == null?null:e.module.getName();
-    }
-
-    public static Expression Expression_cloneWithName(Expression e, Context c, String name, Tokenizer.Token token)
-    {
-        Expression copy;
-        try
-        {
-            copy = e.clone();
-        }
-        catch (CloneNotSupportedException ex)
-        {
-            throw new ExpressionException(c, e, token, "Problems in allocating global function "+name);
-        }
-        return copy.withName(name);
     }
 
     private static TreeSet<String> scarpetFunctions;
     private static TreeSet<String> APIFunctions;
     static
     {
-        Set<String> allFunctions = (new CarpetExpression("null", null, null)).getExpr().getFunctionNames();
+        Set<String> allFunctions = (new CarpetExpression(null, "null", null, null)).getExpr().getFunctionNames();
-        scarpetFunctions = new TreeSet<>(new Expression("null").getFunctionNames());
+        scarpetFunctions = new TreeSet<>(Expression.none.getFunctionNames());
         APIFunctions = allFunctions.stream().filter(s -> !scarpetFunctions.contains(s)).collect(Collectors.toCollection(TreeSet::new));
     }
 
@@ -63,10 +48,8 @@ public class ExpressionInspector
         // not that useful in commandline, more so in external scripts, so skipping here
         //scarpetMatches.addAll(CarpetServer.scriptServer.events.eventHandlers.keySet().stream().
         //        filter(s -> s.startsWith(prefix) && s.length() <= maxLen).map(s -> "__"+s+"(").collect(Collectors.toList()));
-        scarpetMatches.addAll(host.globalFunctions.keySet().stream().
+        scarpetMatches.addAll(host.globaFunctionNames(host.myCode, s -> s.startsWith(prefix)).map(s -> s+"(").collect(Collectors.toList()));
-                filter(s -> s.startsWith(prefix)).map(s -> s+"(").collect(Collectors.toList()));
+        scarpetMatches.addAll(host.globaVariableNames(host.myCode, s -> s.startsWith(prefix)).collect(Collectors.toList()));
-        scarpetMatches.addAll(host.globalVariables.keySet().stream().
-                filter(s -> s.startsWith(prefix)).collect(Collectors.toList()));
         return scarpetMatches;
     }
 }

src/main/java/carpet/script/ScriptHost.java

@@ -1,111 +1,292 @@
 package carpet.script;
 
-import carpet.script.bundled.ModuleInterface;
+import carpet.script.bundled.Module;
+import carpet.script.exception.InternalExpressionException;
 import carpet.script.value.FunctionValue;
 import carpet.script.value.Value;
 import it.unimi.dsi.fastutil.objects.Object2ObjectOpenHashMap;
 
-import java.util.HashSet;
+import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
-import java.util.Set;
+import java.util.function.Predicate;
-import java.util.stream.Collectors;
+import java.util.stream.Stream;
 
 public abstract class ScriptHost
 {
+    public class ModuleData
+    {
+        Module parent;
+        public Map<String, FunctionValue> globalFunctions = new Object2ObjectOpenHashMap<>();
+        public Map<String, LazyValue> globalVariables = new Object2ObjectOpenHashMap<>();
+        public Map<String, ModuleData> functionImports = new Object2ObjectOpenHashMap<>(); // imported functions string to module
+        public Map<String, ModuleData> globalsImports = new Object2ObjectOpenHashMap<>(); // imported global variables string to module
+        public Map<String, ModuleData> futureImports = new Object2ObjectOpenHashMap<>(); // imports not known before used
+
+        public ModuleData(Module parent, ModuleData other)
+        {
+            // imports are just pointers, but they still point to the wrong modules (point to the parent)
+            this.parent = parent;
+            globalFunctions.putAll(other.globalFunctions);
+            other.globalVariables.forEach((key, value) ->
+            {
+                Value var = value.evalValue(null);
+                Value copy = var.deepcopy();
+                copy.boundVariable = var.boundVariable;
+                globalVariables.put(key, (c, t) -> copy);
+            });
+        }
+
+        public void setImportsBasedOn(ScriptHost host, ModuleData other)
+        {
+            // fixing imports
+            other.functionImports.forEach((name, targetData) -> {
+                functionImports.put(name, host.moduleData.get(targetData.parent));
+            });
+            other.globalsImports.forEach((name, targetData) -> {
+                globalsImports.put(name, host.moduleData.get(targetData.parent));
+            });
+            other.futureImports.forEach((name, targetData) -> {
+                futureImports.put(name, host.moduleData.get(targetData.parent));
+            });
+
+        }
+
+        public ModuleData(Module parent)
+        {
+            this.parent = parent;
+        }
+    }
     protected final Map<String, ScriptHost> userHosts = new Object2ObjectOpenHashMap<>();
-    public Map<String, FunctionValue> globalFunctions = new Object2ObjectOpenHashMap<>();
+    private Map<Module,ModuleData> moduleData = new HashMap<>(); // marking imports
-    public Map<String, LazyValue> globalVariables = new Object2ObjectOpenHashMap<>();
+    private Map<String,Module> modules = new HashMap<>();
-    private Set<String> imports = new HashSet<>();
 
     protected ScriptHost parent;
     protected boolean perUser;
 
-    //private String name;
     public String getName() {return myCode==null?null:myCode.getName();}
 
-    protected final ModuleInterface myCode;
+    public final Module myCode;
 
     public Fluff.TriFunction<Expression, Tokenizer.Token, String, List<String>> errorSnooper = null;
 
-    ScriptHost(ModuleInterface code, boolean perUser, ScriptHost parent)
+    protected ScriptHost(Module code, boolean perUser, ScriptHost parent)
     {
         this.parent = parent;
-        //this.name = name;
         this.myCode = code;
         this.perUser = perUser;
-        if (code != null) imports.add(code.getName());
+        ModuleData moduleData = new ModuleData(code);
-        globalVariables.put("euler", (c, t) -> Expression.euler);
+        initializeModuleGlobals(moduleData);
-        globalVariables.put("pi", (c, t) -> Expression.PI);
+        this.moduleData.put(code, moduleData);
-        globalVariables.put("null", (c, t) -> Value.NULL);
+        this.modules.put(code==null?null:code.getName(), code);
-        globalVariables.put("true", (c, t) -> Value.TRUE);
-        globalVariables.put("false", (c, t) -> Value.FALSE);
-
-        //special variables for second order functions so we don't need to check them all the time
-        globalVariables.put("_", (c, t) -> Value.ZERO);
-        globalVariables.put("_i", (c, t) -> Value.ZERO);
-        globalVariables.put("_a", (c, t) -> Value.ZERO);
     }
 
-    public void addUserDefinedFunction(String funName, FunctionValue function)
+    void initializeModuleGlobals(ModuleData md)
     {
-        globalFunctions.put(funName, function);
+        md.globalVariables.put("euler", (c, t) -> Expression.euler);
+        md.globalVariables.put("pi", (c, t) -> Expression.PI);
+        md.globalVariables.put("null", (c, t) -> Value.NULL);
+        md.globalVariables.put("true", (c, t) -> Value.TRUE);
+        md.globalVariables.put("false", (c, t) -> Value.FALSE);
     }
 
-    public boolean importModule(Context c, String moduleName)
+    public void importModule(Context c, String moduleName)
     {
-        if (imports.contains(moduleName)) return false;  // aready imported
+        if (modules.containsKey(moduleName)) return;  // aready imported
-        ModuleInterface module = getModuleByName(moduleName);
+        Module module = getModuleByName(moduleName);
-        if (imports.contains(module.getName())) return false;  // aready imported, once again, in case some discrepancies
+        if (modules.containsKey(module.getName())) return;  // aready imported, once again, in case some discrepancies in names?
-        imports.add(module.getName());
+        modules.put(module.getName(), module);
-        if (runModuleCode(c, module))
+        ModuleData data =  new ModuleData(module);
+        initializeModuleGlobals(data);
+        moduleData.put(module, data);
+        runModuleCode(c, module);
+        //moduleData.remove(module); // we are pooped already, but doesn't hurt to clean that up.
+        //modules.remove(module.getName());
+        //throw new InternalExpressionException("Failed to import a module "+moduleName);
+    }
+    public void importNames(Context c, Module targetModule, String sourceModuleName, List<String> identifiers )
+    {
+        if (!moduleData.containsKey(targetModule))
         {
-            return true;
+            throw new InternalExpressionException("Cannot import to module that doesn't exist");
+        }
+        Module source = modules.get(sourceModuleName);
+        ModuleData sourceData = moduleData.get(source);
+        ModuleData targetData = moduleData.get(targetModule);
+        if (sourceData == null || targetData == null)
+        {
+            throw new InternalExpressionException("Cannot import from module that is not imported");
+        }
+        for (String identifier: identifiers)
+        {
+            if (sourceData.globalFunctions.containsKey(identifier))
+            {
+                targetData.functionImports.put(identifier, sourceData);
+            }
+            else if (sourceData.globalVariables.containsKey(identifier))
+            {
+                targetData.globalsImports.put(identifier, sourceData);
+            }
+            else
+            {
+                targetData.functionImports.put(identifier, sourceData);
+            }
         }
-        imports.remove(module.getName());
-        return false;
     }
 
-    protected abstract ModuleInterface getModuleByName(String name); // this should be shell out in the executuor
+    protected abstract Module getModuleByName(String name); // this should be shell out in the executor
 
-    protected abstract boolean runModuleCode(Context c, ModuleInterface module); // this should be shell out in the executuor
+    protected abstract void runModuleCode(Context c, Module module); // this should be shell out in the executor
 
-    public void delFunction(String funName)
+    public FunctionValue getFunction(String name) { return getFunction(myCode, name); }
+    public FunctionValue getAssertFunction(Module module, String name)
     {
-        globalFunctions.remove(funName);
+        FunctionValue ret = getFunction(module, name);
+        if (ret == null) throw new InternalExpressionException("Function "+name+" is not defined yet");
+        return ret;
+    }
+    private FunctionValue getFunction(Module module, String name)
+    {
+        ModuleData local = moduleData.get(module);
+        FunctionValue ret = local.globalFunctions.get(name); // most uses would be from local scope anyways
+        if (ret != null) return ret;
+        ModuleData target = local.functionImports.get(name);
+        if (target != null)
+        {
+            ret = target.globalFunctions.get(name);
+            if (ret != null) return ret;
+        }
+        // not in local scope - will need to travel over import links
+        target = local.futureImports.get(name);
+        if (target == null) return null;
+        target = findModuleDataFromFunctionImports(name, target, 0);
+        if (target == null) return null;
+        local.futureImports.remove(name);
+        local.functionImports.put(name, target);
+        return target.globalFunctions.get(name);
     }
 
-    public void delGlobalVariable(String varName)
+    private ModuleData findModuleDataFromFunctionImports(String name, ModuleData source, int ttl)
     {
-        globalVariables.remove(varName);
+        if (ttl > 10) throw new InternalExpressionException("Cannot import "+name+", either your imports are too deep or too loopy");
+        if (source.globalFunctions.containsKey(name))
+            return source;
+        if (source.functionImports.containsKey(name))
+            return findModuleDataFromFunctionImports(name, source.functionImports.get(name), ttl+1);
+        if (source.futureImports.containsKey(name))
+            return findModuleDataFromFunctionImports(name, source.futureImports.get(name), ttl+1);
+        return null;
+    }
+
+    public LazyValue getGlobalVariable(String name) { return getGlobalVariable(myCode, name); }
+    public LazyValue getGlobalVariable(Module module, String name)
+    {
+        ModuleData local = moduleData.get(module);
+        LazyValue ret = local.globalVariables.get(name); // most uses would be from local scope anyways
+        if (ret != null) return ret;
+        ModuleData target = local.globalsImports.get(name);
+        if (target != null)
+        {
+            ret = target.globalVariables.get(name);
+            if (ret != null) return ret;
+        }
+        // not in local scope - will need to travel over import links
+        target = local.futureImports.get(name);
+        if (target == null) return null;
+        target = findModuleDataFromGlobalImports(name, target, 0);
+        if (target == null) return null;
+        local.futureImports.remove(name);
+        local.globalsImports.put(name, target);
+        return target.globalVariables.get(name);
+    }
+
+    private ModuleData findModuleDataFromGlobalImports(String name, ModuleData source, int ttl)
+    {
+        if (ttl > 10) throw new InternalExpressionException("Cannot import "+name+", either your imports are too deep or too loopy");
+        if (source.globalVariables.containsKey(name))
+            return source;
+        if (source.globalsImports.containsKey(name))
+            return findModuleDataFromGlobalImports(name, source.globalsImports.get(name), ttl+1);
+        if (source.futureImports.containsKey(name))
+            return findModuleDataFromGlobalImports(name, source.futureImports.get(name), ttl+1);
+        return null;
+    }
+
+    public void delFunctionWithPrefix(Module module, String prefix)
+    {
+        ModuleData data = moduleData.get(module);
+        data.globalFunctions.entrySet().removeIf(e -> e.getKey().startsWith(prefix));
+        data.functionImports.entrySet().removeIf(e -> e.getKey().startsWith(prefix));
+    }
+    public void delFunction(Module module, String funName)
+    {
+        ModuleData data = moduleData.get(module);
+        data.globalFunctions.remove(funName);
+        data.functionImports.remove(funName);
+    }
+
+    public void delGlobalVariableWithPrefix(Module module, String prefix)
+    {
+        ModuleData data = moduleData.get(module);
+        data.globalVariables.entrySet().removeIf(e -> e.getKey().startsWith(prefix));
+        data.globalsImports.entrySet().removeIf(e -> e.getKey().startsWith(prefix));
+    }
+
+    public void delGlobalVariable(Module module, String varName)
+    {
+        ModuleData data = moduleData.get(module);
+        data.globalFunctions.remove(varName);
+        data.functionImports.remove(varName);
+    }
+
+    public void addUserDefinedFunction(Module module, String name, FunctionValue fun)
+    {
+        moduleData.get(module).globalFunctions.put(name, fun);
+    }
+
+    public void setGlobalVariable(Module module, String name, LazyValue lv)
+    {
+        moduleData.get(module).globalVariables.put(name, lv);
+    }
+
+    public Stream<String> globaVariableNames(Module module, Predicate<String> predicate)
+    {
+        return Stream.concat(
+                moduleData.get(module).globalVariables.keySet().stream(),
+                moduleData.get(module).globalsImports.keySet().stream()
+        ).filter(predicate);
+    }
+
+    public Stream<String> globaFunctionNames(Module module, Predicate<String> predicate)
+    {
+        return Stream.concat(
+                moduleData.get(module).globalFunctions.keySet().stream(),
+                moduleData.get(module).functionImports.keySet().stream()
+        ).filter(predicate);
     }
 
     public ScriptHost retrieveForExecution(String /*Nullable*/ user)
     {
-        if (!perUser)
+        if (!perUser) return this;
-            return this;
+        ScriptHost oldUserHost = userHosts.get(user);
-        ScriptHost userHost = userHosts.get(user);
+        if (oldUserHost != null) return oldUserHost;
-        if (userHost != null)
+        ScriptHost userHost = this.duplicate();
-            return userHost;
+        userHost.modules.putAll(this.modules);
-        userHost = this.duplicate();
+        for (Map.Entry<Module, ScriptHost.ModuleData> e : this.moduleData.entrySet())
-        userHost.globalVariables.putAll(this.globalVariables);
+        {
-        userHost.globalFunctions.putAll(this.globalFunctions);
+            userHost.moduleData.put(e.getKey(), new ModuleData(e.getKey(), e.getValue()));
-        userHost.imports.addAll(this.imports);
+        }
+        // fixing imports
+        userHost.moduleData.forEach((module, data) ->
+        {
+            data.setImportsBasedOn(this, this.moduleData.get(data.parent));
+        });
         userHosts.put(user, userHost);
         return userHost;
     }
 
     protected abstract ScriptHost duplicate();
 
-    public List<String> getPublicFunctions()
-    {
-        return globalFunctions.keySet().stream().filter((str) -> !str.startsWith("_")).sorted().collect(Collectors.toList());
-    }
-    public List<String> getAvailableFunctions(boolean all)
-    {
-        return globalFunctions.keySet().stream().filter((str) -> all || !str.startsWith("__")).sorted().collect(Collectors.toList());
-    }
-
     public void onClose() { }
 
     public void setPerPlayer(boolean isPerUser)

src/main/java/carpet/script/bundled/BundledModule.java

@@ -6,7 +6,7 @@ import java.io.IOException;
 import java.nio.charset.StandardCharsets;
 import java.util.Locale;
 
-public class BundledModule implements ModuleInterface
+public class BundledModule extends Module
 {
     private String name;
     private String code;

src/main/java/carpet/script/bundled/FileModule.java

@@ -14,7 +14,7 @@ import java.io.IOException;
 import java.nio.file.Files;
 import java.util.Locale;
 
-public class FileModule implements ModuleInterface
+public class FileModule extends Module
 {
     private String name;
     private String code;

src/main/java/carpet/script/bundled/Module.java

@@ -10,13 +10,13 @@ import java.nio.file.Files;
 import static carpet.script.bundled.FileModule.read;
 import static carpet.script.bundled.FileModule.write;
 
-public interface ModuleInterface
+public abstract class Module
 {
-    String getName();
+    public abstract String getName();
-    String getCode();
+    public abstract String getCode();
-    default boolean isInternal() {return true; }
+    public boolean isInternal() {return true; }
 
-    default Tag getData(String file)
+    public Tag getData(String file)
     {
         File dataFile = CarpetServer.minecraft_server.getLevelStorage().resolveFile(
                 CarpetServer.minecraft_server.getLevelName(), "scripts/"+getName()+".data"+(file==null?"":"."+file)+".nbt");
@@ -24,7 +24,7 @@ public interface ModuleInterface
         return read(dataFile);
     }
 
-    default void saveData(String file, Tag globalState)
+    public void saveData(String file, Tag globalState)
     {
         File dataFile =CarpetServer.minecraft_server.getLevelStorage().resolveFile(
                 CarpetServer.minecraft_server.getLevelName(), "scripts/"+getName()+".data"+(file==null?"":"."+file)+".nbt");
@@ -41,4 +41,10 @@ public interface ModuleInterface
         write(globalState, dataFile);
 
     }
+
+    @Override
+    public int hashCode()
+    {
+        return getName().hashCode();
+    }
 }

src/main/java/carpet/script/exception/CarpetExpressionException.java

@@ -6,7 +6,7 @@ import net.minecraft.server.command.ServerCommandSource;
 
 import java.util.List;
 
-public class CarpetExpressionException extends RuntimeException
+public class CarpetExpressionException extends RuntimeException implements ResolvedException
 {
     public final List<FunctionValue> stack;
 

src/main/java/carpet/script/exception/ExpressionException.java

@@ -10,16 +10,17 @@ import java.util.ArrayList;
 import java.util.List;
 
 import static carpet.script.ExpressionInspector.Expression_getExpressionSnippet;
-import static carpet.script.ExpressionInspector.Expression_getName;
+import static carpet.script.ExpressionInspector.Expression_getModuleName;
 
 /* The expression evaluators exception class. */
-public class ExpressionException extends RuntimeException
+public class ExpressionException extends RuntimeException implements ResolvedException
 {
     public final Context context;
     public final List<FunctionValue> stack = new ArrayList<>();
-    public ExpressionException(Context c, String message)
+
+    public ExpressionException(Context c, Expression e, String message)
     {
-        super(makeMessage(c, null, null, message));
+        super(makeMessage(c, e, null, message));
         context = c;
     }
 
@@ -35,11 +36,12 @@ public class ExpressionException extends RuntimeException
         context = c;
     }
 
-    private static final Fluff.TriFunction<Expression, Tokenizer.Token, String, List<String>> errorMaker = (expr, token, errmessage) ->
+    private static final Fluff.TriFunction<Expression, Tokenizer.Token, String, List<String>> errorMaker = (expr, /*Nullable*/ token, errmessage) ->
     {
 
         List<String> errMsg = new ArrayList<>();
-        if (expr != null && token != null)
+        errmessage += Expression_getModuleName(expr) == null?"":(" in "+Expression_getModuleName(expr));
+        if (token != null)
         {
             List<String> snippet = Expression_getExpressionSnippet(token, expr);
             errMsg.addAll(snippet);
@@ -52,11 +54,6 @@ public class ExpressionException extends RuntimeException
             {
                 errmessage += " at pos " + (token.pos + 1);
             }
-            if (Expression_getName(expr) != null)
-            {
-                errmessage += " (" + Expression_getName(expr) + ")";
-            }
-
         }
         errMsg.add(errmessage);
         return errMsg;

src/main/java/carpet/script/exception/ResolvedException.java

@@ -0,0 +1,5 @@
+package carpet.script.exception;
+
+public interface ResolvedException
+{
+}

src/main/java/carpet/script/value/FunctionValue.java

@@ -6,7 +6,6 @@ import carpet.script.ExpressionInspector;
 import carpet.script.Fluff;
 import carpet.script.LazyValue;
 import carpet.script.Tokenizer;
-import carpet.script.bundled.ModuleInterface;
 import carpet.script.exception.BreakStatement;
 import carpet.script.exception.ContinueStatement;
 import carpet.script.exception.ExitStatement;
@@ -128,11 +127,9 @@ public class FunctionValue extends Value implements Fluff.ILazyFunction
 
     public LazyValue callInContext(Expression callingExpression, Context c, Integer type, Expression e, Tokenizer.Token t, List<LazyValue> lazyParams)
     {
-        // this hole thing might not be really needed (errata: needed to know the package to report with exceptions
-        Expression callContext = ExpressionInspector.Expression_cloneWithName(e, c, fullName(), t);
         try
         {
-            return lazyEval(c, type, callContext, t, lazyParams);
+            return lazyEval(c, type, e, t, lazyParams);
         }
         catch (ExpressionException exc)
         {
@@ -142,12 +139,12 @@ public class FunctionValue extends Value implements Fluff.ILazyFunction
         catch (InternalExpressionException exc)
         {
             exc.stack.add(this);
-            throw new ExpressionException(c, callContext, t, exc.getMessage(), exc.stack);
+            throw new ExpressionException(c, e, t, exc.getMessage(), exc.stack);
         }
 
         catch (ArithmeticException exc)
         {
-            throw new ExpressionException(c, callContext, t, "Your math is wrong, "+exc.getMessage(), Collections.singletonList(this));
+            throw new ExpressionException(c, e, t, "Your math is wrong, "+exc.getMessage(), Collections.singletonList(this));
         }
     }
 
@@ -190,14 +187,10 @@ public class FunctionValue extends Value implements Fluff.ILazyFunction
             retVal = throwStatement.retval;
             rethrow = true;
         }
-        catch (ArithmeticException | ExitStatement | ExpressionException | InternalExpressionException exc )
+        //catch (ArithmeticException | ExitStatement | ExpressionException | InternalExpressionException exc )
-        {
+        //{
-            throw exc; // rethrow so could be contextualized if needed
+        //    throw exc; // rethrow so could be contextualized if needed
-        }
+        //}
-        catch (Exception exc)
-        {
-            throw new ExpressionException(c, e, t, "Error while evaluating expression: "+exc.getMessage());
-        }
         if (rethrow)
         {
             throw new ThrowStatement(retVal);