Refactoring

Src/AST/Myc.Ast.Evaluator.pas

@@ -126,8 +126,6 @@ var
     i: Integer;
     sourceAddresses: TArray<TResolvedAddress>;
     closureScope: IExecutionScope;
-    [weak]
-    closure: TDataValue.TFunc;
     visitorFactory: TVisitorFactory;
 begin
     sourceAddresses := Node.Upvalues;
@@ -146,7 +144,9 @@ begin
     var scopeDescriptor := Node.ScopeDescriptor;
     var params := Node.Parameters;
 
-    // weak reference to break cyclic referencing
+    // declare closure as weak to break cyclic referencing when it is captured by itself
+    var [weak] closure: TDataValue.TFunc;
+
     closure :=
         TDataValue.TFunc(
             function(const ArgValues: TArray<TDataValue>): TDataValue
@@ -182,35 +182,37 @@ begin
             end
         );
 
-    Result := TDataValue(closure);
+    Result := closure;
 end;
 
 function TEvaluatorVisitor.VisitFunctionCall(const Node: IFunctionCallNode): TDataValue;
 var
     calleeValue: TDataValue;
+    [weak]
+    callee: TDataValue.TFunc;
 begin
     calleeValue := Node.Callee.Accept(Self);
 
-    if calleeValue.Kind <> vkMethod then
+    case calleeValue.Kind of
+        vkMethod: callee := calleeValue.AsMethod();
+    else
         raise EArgumentException.Create('Expression is not invokable in this context.');
+    end;
 
     var argNodes := Node.Arguments;
     case Length(argNodes) of
-        0: Result := (calleeValue.AsMethod)([]);
-        1: Result := (calleeValue.AsMethod)([argNodes[0].Accept(Self)]);
-        2: Result := (calleeValue.AsMethod)([argNodes[0].Accept(Self), argNodes[1].Accept(Self)]);
-        3: Result := (calleeValue.AsMethod)([argNodes[0].Accept(Self), argNodes[1].Accept(Self), argNodes[2].Accept(Self)]);
-        4:
-            Result :=
-                (calleeValue.AsMethod)
-                    ([argNodes[0].Accept(Self), argNodes[1].Accept(Self), argNodes[2].Accept(Self), argNodes[3].Accept(Self)]);
+        0: Result := callee([]);
+        1: Result := callee([argNodes[0].Accept(Self)]);
+        2: Result := callee([argNodes[0].Accept(Self), argNodes[1].Accept(Self)]);
+        3: Result := callee([argNodes[0].Accept(Self), argNodes[1].Accept(Self), argNodes[2].Accept(Self)]);
+        4: Result := callee([argNodes[0].Accept(Self), argNodes[1].Accept(Self), argNodes[2].Accept(Self), argNodes[3].Accept(Self)]);
     else
         var argValues: TArray<TDataValue>;
         SetLength(argValues, Length(argNodes));
         for var i := 0 to High(argNodes) do
             argValues[i] := argNodes[i].Accept(Self);
 
-        Result := (calleeValue.AsMethod)(argValues);
+        Result := callee(argValues);
     end;
 end;