Nop-Node

Src/AST/Myc.Ast.Nodes.pas

@@ -37,6 +37,7 @@ type
     IAddSeriesItemNode = interface;
     ISeriesLengthNode = interface;
     IRecurNode = interface;
+    INopNode = interface; // Added Nop
 
     // Defines the concrete kinds of AST nodes
     TAstNodeKind = (
@@ -63,7 +64,8 @@ type
         akCreateSeries,
         akAddSeriesItem,
         akSeriesLength,
-        akRecur
+        akRecur,
+        akNop // Added Nop
     );
 
     // --- Concrete Type Definitions ---
@@ -113,6 +115,7 @@ type
         function VisitAddSeriesItem(const Node: IAddSeriesItemNode): TDataValue;
         function VisitSeriesLength(const Node: ISeriesLengthNode): TDataValue;
         function VisitRecurNode(const Node: IRecurNode): TDataValue;
+        function VisitNop(const Node: INopNode): TDataValue; // Added Nop
     end;
 
     IAstNode = interface(IInterface)
@@ -145,10 +148,16 @@ type
         function AsAddSeriesItem: IAddSeriesItemNode;
         function AsSeriesLength: ISeriesLengthNode;
         function AsRecur: IRecurNode;
+        function AsNop: INopNode; // Added Nop
 
         property Kind: TAstNodeKind read GetKind;
     end;
 
+    INopNode = interface(IAstNode)
+    // A placeholder node for the UI (e.g., drag target).
+    // This node is illegal during compilation.
+    end;
+
     IConstantNode = interface(IAstNode)
         // Represents a constant value in the AST (Scalar, Text, or Void).
         {$region 'private'}