Only inherit globals

snap-compile/src/test/java/org/snapscript/compile/ScopeInheritanceTest.java

@@ -0,0 +1,20 @@
+package org.snapscript.compile;
+
+import junit.framework.TestCase;
+
+public class ScopeInheritanceTest extends ScriptTestCase {
+
+   private static final String SOURCE =
+    "for(i in 0..2){\n"+
+    "   fun(i);\n"+
+    "}\n"+
+    "\n"+
+    "func fun(i){\n"+
+    "   println(i);\n"+
+    "}\n";
+
+   public void testInheritance() throws Exception {
+      assertScriptCompiles(SOURCE);
+   }
+
+}

snap-core/src/main/java/org/snapscript/core/constraint/Constraint.java

@@ -79,7 +79,7 @@ public boolean isConstant() {
       return false;
    }   
 
-   public boolean isWild() {
+   public boolean isStatic() {
       return false;
    }   
 

snap-core/src/main/java/org/snapscript/core/constraint/DeclarationConstraint.java

@@ -92,12 +92,17 @@ public boolean isModule() {
    public boolean isPrivate() {
       return ModifierType.isPrivate(modifiers);
    }
-   
+
    @Override
    public boolean isConstant() {
       return ModifierType.isConstant(modifiers);
    }
-
+
+   @Override
+   public boolean isStatic() {
+      return ModifierType.isStatic(modifiers);
+   }
+
    @Override
    public String toString() {
       return String.valueOf(constraint);

snap-core/src/main/java/org/snapscript/core/error/CompileErrorFormatter.java

@@ -34,6 +34,16 @@ public String formatAccessError(Type type, String name) {
 
       return builder.toString();
    }
+
+   public String formatReferenceError(String name) {
+      StringBuilder builder = new StringBuilder();
+
+      builder.append("Property '");
+      builder.append(name);
+      builder.append("' not found in scope");
+
+      return builder.toString();
+   }
 
    public String formatReferenceError(Type type, String name) {
       StringBuilder builder = new StringBuilder();

snap-core/src/main/java/org/snapscript/core/error/CompileErrorHandler.java

@@ -39,7 +39,12 @@ public Result handleGenericError(Scope scope, String name, Type[] list) {
       String message = formatter.formatGenericError(name, list);
       throw builder.createInternalException(message);
    }
-
+
+   public Result handleReferenceError(Scope scope, String name) {
+      String message = formatter.formatReferenceError(name);
+      throw builder.createInternalException(message);
+   }
+
    public Result handleReferenceError(Scope scope, Type type, String name) {
       String message = formatter.formatReferenceError(type, name);
       throw builder.createInternalException(message);

snap-core/src/main/java/org/snapscript/core/error/ErrorHandler.java

@@ -31,7 +31,7 @@ public Result failCompileConstruction(Scope scope, Type type) {
    }
 
    public Result failCompileReference(Scope scope, String name) {
-      return compile.handleAccessError(scope, name);
+      return compile.handleReferenceError(scope, name);
    }
 
    public Result failCompileAccess(Scope scope, Type type, String name) {

snap-core/src/main/java/org/snapscript/core/scope/index/Local.java

@@ -1,20 +1,22 @@
 package org.snapscript.core.scope.index;
 
+import static org.snapscript.core.constraint.Constraint.NONE;
+
 import org.snapscript.core.constraint.Constraint;
 import org.snapscript.core.variable.Value;
 
 public abstract class Local extends Value {
-   
+
    public static Local getConstant(Object value, String name) {
-      return new LocalConstant(value, name, null);
+      return new LocalConstant(value, name, NONE);
    }
-   
+
    public static Local getConstant(Object value, String name, Constraint type) {
       return new LocalConstant(value, name, type);
    }
 
    public static Local getReference(Object value, String name) {
-      return new LocalReference(value, name, null);
+      return new LocalReference(value, name, NONE);
    }
 
    public static Local getReference(Object value, String name, Constraint type) {

snap-core/src/main/java/org/snapscript/core/scope/index/LocalScopeExtractor.java

@@ -9,10 +9,16 @@ public class LocalScopeExtractor {
 
    private final boolean reference;
    private final boolean extension;
+   private final boolean globals;
 
    public LocalScopeExtractor(boolean reference, boolean extension) {
+      this(reference, extension, false);
+   }
+
+   public LocalScopeExtractor(boolean reference, boolean extension, boolean globals) {
       this.reference = reference;
       this.extension = extension;
+      this.globals = globals;
    }
 
    public Scope extract(Scope scope) {
@@ -33,17 +39,20 @@ public Scope extract(Scope original, Scope outer) {
 
          for(Local local : table){
             String name = local.getName();
-            Value value = inner.getValue(name);
-
-            if(value == null) {
-               if(reference) {
-                  inner.addValue(name, local); // enable modification of local
-               } else {
-                  Object object = local.getValue();
-                  Constraint constraint = local.getConstraint();
-                  Value constant = Value.getConstant(object, constraint);
-
-                  inner.addValue(name, constant); // local is a visible constant
+            Constraint constraint = local.getConstraint();
+
+            if(!globals || constraint.isStatic()) {
+               Value value = inner.getValue(name);
+
+               if (value == null) {
+                  if (reference) {
+                     inner.addValue(name, local); // enable modification of local
+                  } else {
+                     Object object = local.getValue();
+                     Value constant = Value.getConstant(object, constraint);
+
+                     inner.addValue(name, constant); // local is a visible constant
+                  }
                }
             }
          }

snap-parse/src/main/resources/grammar.txt

@@ -347,12 +347,15 @@ module-function = <annotation-list><access-modifier-list><function-name>'('<para
 module-statement = {<try-statement> | <synchronized-statement> | <conditional-statement> | <type-definition> | <assignment-statement> | <expression-statement>};
 module-part = {<module-import> | <module-function> | <module-declaration> | <module-statement>};
 module-definition = ?<annotation-list>'module'_<module-name>{'{}' | '{'*<module-part>'}'};
-
+
+global = <assignment-variable>?(':'<constraint>?_)?('='<assignment-expression>);
+global-statement = <declaration-modifier>_<global>*(','<global>)';';
+
 script-import = <import-static> | <import> | <import-list>;
 script-function = {'function'|'func'}_<function-name>'('<parameter-list>')'?(':'<constraint>)<group-statement>;
 script-statement = { <try-statement> | 
 				     <synchronized-statement> |
-				     <declaration-statement> |
+				     <global-statement> |
 				     <assert-statement> |
 				     <debug-statement> | 
 				     <conditional-statement> | 

snap-tree/src/main/java/org/snapscript/tree/Global.java

@@ -0,0 +1,36 @@
+package org.snapscript.tree;
+
+import static org.snapscript.core.ModifierType.*;
+
+import org.snapscript.core.Evaluation;
+import org.snapscript.core.constraint.Constraint;
+import org.snapscript.core.scope.Scope;
+import org.snapscript.core.variable.Value;
+import org.snapscript.tree.literal.TextLiteral;
+
+public class Global extends Declaration {
+
+   public Global(TextLiteral identifier) {
+      this(identifier, null, null);
+   }
+
+   public Global(TextLiteral identifier, Constraint constraint) {
+      this(identifier, constraint, null);
+   }
+
+   public Global(TextLiteral identifier, Evaluation value) {
+      this(identifier, null, value);
+   }
+
+   public Global(TextLiteral identifier, Constraint constraint, Evaluation value) {
+      super(identifier, constraint, value);
+   }
+
+   public Value compile(Scope scope, int modifiers) throws Exception {
+      return super.compile(scope, modifiers | STATIC.mask | PUBLIC.mask);
+   }
+
+   public Value declare(Scope scope, int modifiers) throws Exception {
+      return super.declare(scope, modifiers | STATIC.mask | PUBLIC.mask);
+   }
+}

snap-tree/src/main/java/org/snapscript/tree/compile/FunctionScopeCompiler.java

@@ -1,5 +1,7 @@
 package org.snapscript.tree.compile;
 
+import static org.snapscript.core.ModifierType.STATIC;
+
 import java.util.List;
 
 import org.snapscript.core.constraint.Constraint;
@@ -16,7 +18,11 @@ public class FunctionScopeCompiler extends ScopeCompiler {
    protected final GenericList generics;
 
    public FunctionScopeCompiler(GenericList generics) {
-      this.extractor = new LocalScopeExtractor(false, true);
+      this(generics, false);
+   }
+
+   public FunctionScopeCompiler(GenericList generics, boolean globals) {
+      this.extractor = new LocalScopeExtractor(false, true, globals);
       this.generics = generics;
    }
 

snap-tree/src/main/java/org/snapscript/tree/script/ScriptFunction.java

@@ -38,7 +38,7 @@ public ScriptFunction(FunctionName identifier, ParameterList parameters, Stateme
    public ScriptFunction(FunctionName identifier, ParameterList parameters, Constraint constraint, Statement body){
       this.reference = new AtomicReference<FunctionBody>();
       this.constraint = new DeclarationConstraint(constraint);
-      this.compiler = new FunctionScopeCompiler(identifier);
+      this.compiler = new FunctionScopeCompiler(identifier, true);
       this.builder = new ScriptFunctionBuilder(body);
       this.execution = new NoExecution(NORMAL);
       this.identifier = identifier;

snap-tree/src/main/resources/instruction.txt

@@ -68,6 +68,8 @@ map-entry-list = org.snapscript.tree.construct.MapEntryList
 map-entry = org.snapscript.tree.construct.MapEntry
 map-key = org.snapscript.tree.construct.MapKey
 collection-index = org.snapscript.tree.collection.CollectionIndex
+global = org.snapscript.tree.Global
+global-statement = org.snapscript.tree.DeclarationStatement
 declaration = org.snapscript.tree.Declaration
 declaration-modifier = org.snapscript.tree.Modifier
 declaration-statement = org.snapscript.tree.DeclarationStatement