Refactoring for immutable nodes

Src/AST/Myc.Ast.MacroExpander.pas

@@ -113,9 +113,9 @@ begin
     try
         for var node in ANodes do
         begin
-            if (node is TUnquoteSplicingNode) then
+            if node.Kind = akUnquoteSplicing then
             begin
-                var spliceExpr := (node as TUnquoteSplicingNode).Expression;
+                var spliceExpr := node.AsUnquoteSplicing.Expression;
                 // Evaluate the unquoted expression
                 var evaluatedSpliceValue := FEvaluate(spliceExpr);
 
@@ -158,9 +158,9 @@ begin
     expr := Node.Expression;
 
     // Check if we are unquoting a macro parameter (simple identifier)
-    if (expr is TIdentifierNode) then
+    if expr.Kind = akIdentifier then
     begin
-        symbol := FMacroScope.CreateDescriptor.FindSymbol((expr as TIdentifierNode).Name);
+        symbol := FMacroScope.CreateDescriptor.FindSymbol(expr.AsIdentifier.Name);
         if (symbol.Address.Kind = akLocalOrParent) and (symbol.Address.ScopeDepth = 0) then
         begin
             // It's a parameter. Return the TDataValue containing the AST node passed as argument.
@@ -269,7 +269,7 @@ end;
 
 function TMacroExpander.VisitFunctionCall(const Node: IFunctionCallNode): IAstNode;
 var
-    calleeIdentifier: TIdentifierNode;
+    calleeIdentifier: IIdentifierNode;
     macroDef: IMacroDefinitionNode;
     i: Integer;
 begin
@@ -277,7 +277,7 @@ begin
     if Node.Callee.Kind <> akIdentifier then
         exit(inherited VisitFunctionCall(Node));
 
-    calleeIdentifier := Node.Callee as TIdentifierNode;
+    calleeIdentifier := Node.Callee.AsIdentifier;
 
     // Check if this identifier is a macro
     macroDef := FCurrentDescriptor.FindMacro(calleeIdentifier.Name);