Macro expander integrated in binder

Src/AST/Myc.Ast.JSON.pas

@@ -24,7 +24,7 @@ type
     private
         FJsonObjectStack: TStack<TJSONObject>;
         procedure DataValueToJson(const AValue: TDataValue; const AParent: TJSONObject; const AName: string);
-        function JsonToNode(const AJson: TJSONValue): IAstNode;
+        function JsonToNode(const AJson: TJSONValue; const ExpectedType: String = ''): IAstNode;
         function JsonToDataValue(const AObj: TJSONObject; const AName: string): TDataValue;
 
         function JsonToConstantNode(const AObj: TJSONObject): IConstantNode;
@@ -276,7 +276,6 @@ var
     param: IIdentifierNode;
     i: Integer;
 begin
-    // Added serialization for macro definitions.
     Node.Name.Accept(Self);
     for param in Node.Parameters do
         param.Accept(Self);
@@ -719,7 +718,7 @@ function TJsonAstConverter.JsonToMacroDefNode(const AObj: TJSONObject): IMacroDe
 var
     name: IIdentifierNode;
     params: TArray<IIdentifierNode>;
-    body: IAstNode;
+    body: IQuasiquoteNode;
     paramArray: TJSONArray;
     i: Integer;
 begin
@@ -731,7 +730,7 @@ begin
     for i := 0 to paramArray.Count - 1 do
         params[i] := JsonToIdentifierNode(paramArray.Items[i] as TJSONObject);
 
-    body := JsonToNode(AObj.GetValue('Body'));
+    body := IQuasiquoteNode(JsonToNode(AObj.GetValue('Body'), 'Quasiquote'));
     Result := TAst.MacroDef(name, params, body);
 end;
 
@@ -874,7 +873,7 @@ begin
     Result := TAst.SeriesLength(JsonToIdentifierNode(AObj.GetValue('Series') as TJSONObject));
 end;
 
-function TJsonAstConverter.JsonToNode(const AJson: TJSONValue): IAstNode;
+function TJsonAstConverter.JsonToNode(const AJson: TJSONValue; const ExpectedType: String = ''): IAstNode;
 var
     obj: TJSONObject;
     nodeType: string;
@@ -885,6 +884,9 @@ begin
     obj := AJson as TJSONObject;
     nodeType := obj.GetValue<string>('NodeType');
 
+    if (ExpectedType <> '') and (nodeType <> ExpectedType) then
+        raise EInvalidCast.CreateFmt('Expected a JSON object of type %s for deserialization, but got a %s.', [ExpectedType, nodeType]);
+
     if nodeType = 'Constant' then
         Result := JsonToConstantNode(obj)
     else if nodeType = 'Identifier' then