AST Identities

Src/AST/Myc.Ast.Compiler.TCO.pas

@@ -75,7 +75,7 @@ function TAstTCO.Execute(const RootNode: IAstNode): IAstNode;
 begin
     Result := Accept(RootNode);
     if not Assigned(Result) then
-        Result := TAst.Block([]);
+        Result := TAst.Block([], nil);
 end;
 
 function TAstTCO.Accept(const Node: IAstNode): IAstNode;
@@ -117,7 +117,8 @@ begin
     if newExprs = Node.Expressions then
         Result := Node
     else
-        Result := TAst.Block(newExprs, Node.StaticType);
+        // CoW: Reuse Identity
+        Result := TAst.Block(Node.Identity, newExprs, Node.StaticType);
 end;
 
 function TAstTCO.VisitIfExpression(const Node: IIfExpressionNode): IAstNode;
@@ -139,7 +140,8 @@ begin
     if (newCond = Node.Condition) and (newThen = Node.ThenBranch) and (newElse = Node.ElseBranch) then
         Result := Node
     else
-        Result := TAst.IfExpr(newCond, newThen, newElse, Node.StaticType);
+        // CoW: Reuse Identity
+        Result := TAst.IfExpr(Node.Identity, newCond, newThen, newElse, Node.StaticType);
 end;
 
 function TAstTCO.VisitTernaryExpression(const Node: ITernaryExpressionNode): IAstNode;
@@ -161,7 +163,8 @@ begin
     if (newCond = Node.Condition) and (newThen = Node.ThenBranch) and (newElse = Node.ElseBranch) then
         Result := Node
     else
-        Result := TAst.TernaryExpr(newCond, newThen, newElse, Node.StaticType);
+        // CoW: Reuse Identity
+        Result := TAst.TernaryExpr(Node.Identity, newCond, newThen, newElse, Node.StaticType);
 end;
 
 function TAstTCO.VisitLambdaExpression(const Node: ILambdaExpressionNode): IAstNode;
@@ -183,8 +186,10 @@ begin
     begin
         // Rebuild using factory.
         // IMPORTANT: Pass Layout AND Descriptor (TCO runs after TypeChecker).
+        // CoW: Reuse Identity
         Result :=
             TAst.LambdaExpr(
+                Node.Identity,
                 newParams,
                 newBody,
                 Node.Layout,
@@ -211,7 +216,8 @@ begin
     if newArgs = Node.Arguments then
         Result := Node
     else
-        Result := TAst.Recur(newArgs, Node.StaticType);
+        // CoW: Reuse Identity
+        Result := TAst.Recur(Node.Identity, newArgs, Node.StaticType);
 end;
 
 function TAstTCO.VisitMacroExpansionNode(const Node: IMacroExpansionNode): IAstNode;
@@ -225,7 +231,8 @@ begin
     if newBody = Node.ExpandedBody then
         Result := Node
     else
-        Result := TAst.MacroExpansionNode(Node.CallNode, newBody);
+        // CoW: Reuse Identity
+        Result := TAst.MacroExpansionNode(Node.Identity, Node.CallNode, newBody);
 end;
 
 function TAstTCO.VisitFunctionCall(const Node: IFunctionCallNode): IAstNode;
@@ -249,8 +256,10 @@ begin
     end;
 
     // Use factory to create new node, passing the *new* TCO status
+    // CoW: Reuse Identity
     Result :=
         TAst.FunctionCall(
+            Node.Identity,
             newCallee,
             newArgs,
             Node.StaticType,