Refactoring for immutable nodes

Src/AST/Myc.Ast.Binding.pas

@@ -172,9 +172,9 @@ end;
 function TAstBinder.VisitFunctionCall(const Node: IFunctionCallNode): IAstNode;
 begin
     // --- Transformation: Keyword-as-Function ---
-    if (Node.Callee is TKeywordNode) then
+    if Node.Callee.Kind = akKeyword then
     begin
-        var keywordNode := (Node.Callee as TKeywordNode);
+        var keywordNode := Node.Callee.AsKeyword;
         if Length(Node.Arguments) <> 1 then
             raise EArgumentException.CreateFmt(
                 'Keyword :%s expects exactly one argument (the record/map), but got %d',

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

@@ -117,11 +117,10 @@ end;
 function TAstTCO.VisitBlockExpression(const Node: IBlockExpressionNode): IAstNode;
 var
     isContextTail: Boolean;
-    newExprs: TArray<IAstNode>; // For CoW
+    newExprs: TArray<IAstNode>;
 begin
     isContextTail := FIsTailStack.Peek;
 
-    // Call the base implementation which handles CoW
     var nTail := High(Node.Expressions);
     newExprs :=
         AcceptNodes(
@@ -237,20 +236,17 @@ end;
 
 function TAstTCO.VisitMacroExpansionNode(const Node: IMacroExpansionNode): IAstNode;
 var
-    N: TMacroExpansionNode;
     newBody: IAstNode;
 begin
-    N := (Node as TMacroExpansionNode);
-
     // Propagate tail call status to the expanded body
     FNextIsTail := FIsTailStack.Peek;
-    newBody := Accept(N.ExpandedBody);
+    newBody := Accept(Node.ExpandedBody);
 
-    if newBody = N.ExpandedBody then
+    if newBody = Node.ExpandedBody then
         Result := Node
     else
         // Rebuild, preserving the original CallNode metadata
-        Result := TMacroExpansionNode.Create(N.CallNode, newBody, newBody.AsTypedNode.StaticType);
+        Result := TMacroExpansionNode.Create(Node.CallNode, newBody.AsTypedNode);
 end;
 
 function TAstTCO.VisitFunctionCall(const Node: IFunctionCallNode): IAstNode;

Src/AST/Myc.Ast.JSON.pas

@@ -739,11 +739,7 @@ begin
     for i := 0 to fieldsArray.Count - 1 do
     begin
         fieldObj := fieldsArray.Items[i] as TJSONObject;
-        fields[i] :=
-            TRecordFieldLiteral.Create(
-                TKeywordNode.Create(TKeywordRegistry.Intern(fieldObj.GetValue<string>('Name'))),
-                JsonToNode(fieldObj.GetValue('Value'))
-            );
+        fields[i] := TRecordFieldLiteral.Create(TAst.Keyword(fieldObj.GetValue<string>('Name')), JsonToNode(fieldObj.GetValue('Value')));
     end;
     Result := TAst.RecordLiteral(fields);
 end;

Src/AST/Myc.Ast.Lowering.pas

@@ -85,16 +85,16 @@ end;
 
 function TAstLowerer.VisitFunctionCall(const Node: IFunctionCallNode): IAstNode;
 var
-    calleeIdentifier: TIdentifierNode;
+    calleeIdentifier: IIdentifierNode;
     binaryOp: TScalar.TBinaryOp;
     unaryOp: TScalar.TUnaryOp;
     left, right: IAstNode;
     nodeType: IStaticType;
 begin
     // --- Optimization: Operator Folding ---
-    if (Node.Callee is TIdentifierNode) then
+    if Node.Callee.Kind = akIdentifier then
     begin
-        calleeIdentifier := Node.Callee as TIdentifierNode;
+        calleeIdentifier := Node.Callee.AsIdentifier;
         // Get the type *before* replacing the node (it's an IAstTypedNode)
         nodeType := Node.AsTypedNode.StaticType;
 

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);

Src/AST/Myc.Ast.Nodes.pas

@@ -132,6 +132,7 @@ type
     IAstNode = interface(IInterface)
         {$region 'private'}
         function GetKind: TAstNodeKind;
+        function GetIsTyped: Boolean;
         {$endregion}
         function Accept(const Visitor: IAstVisitor): TDataValue;
 
@@ -164,6 +165,7 @@ type
         function AsBoundIdentifierNode: IBoundIdentifierNode;
         function AsTypedNode: IAstTypedNode;
 
+        property IsTyped: Boolean read GetIsTyped;
         property Kind: TAstNodeKind read GetKind;
     end;
 

Src/AST/Myc.Ast.Scope.pas

@@ -112,6 +112,7 @@ type
             TScopeItem = record
                 Value: TDataValue;
                 IsBoxed: Boolean;
+                function GetContent: TDataValue;
             end;
 
     private
@@ -606,7 +607,6 @@ end;
 
 procedure TScopeDescriptor.PopulateFromScope(Scope: TExecutionScope);
 var
-    val: TDataValue;
     i: Integer;
 begin
     // Recreate descriptor by iterating all defined symbols in the runtime scope.
@@ -627,11 +627,16 @@ begin
         // FSlotTypes[slotIndex] remains TTypes.Unknown.
 
         // Check if the symbol is also a macro and add it to the macro table.
-        val := Scope.ValuesArray[slotIndex].Value;
-        if (val.Kind = vkInterface) and (val.AsIntf<IAstNode> is TMacroDefinitionNode) then
+
+        var val := Scope.ValuesArray[slotIndex].GetContent;
+        if val.Kind = vkInterface then
         begin
-            if not FMacros.ContainsKey(name) then
-                FMacros.Add(name, val.AsIntf<IMacroDefinitionNode>);
+            var node := val.AsIntf<IAstNode>;
+            if (node <> nil) and (node.Kind = akMacroDefinition) then
+            begin
+                if not FMacros.ContainsKey(name) then
+                    FMacros.Add(name, node.AsMacroDefinition);
+            end;
         end;
     end;
 end;
@@ -652,4 +657,11 @@ begin
     Result := TExecutionScope.Create(Parent, Descriptor, CapturedUpvalues);
 end;
 
+function TExecutionScope.TScopeItem.GetContent: TDataValue;
+begin
+    Result := Value;
+    if IsBoxed then
+        Result := Result.AsIntf<IValueCell>.Value;
+end;
+
 end.

Src/AST/Myc.Ast.Script.pas

@@ -511,7 +511,7 @@ begin
                 raise Exception.Create('Syntax Error: Missing value for key ' + fieldName + ' in record literal.');
             fieldValue := ParseExpression.Node;
 
-            fields.Add(TRecordFieldLiteral.Create(TKeywordNode.Create(TKeywordRegistry.Intern(fieldName)), fieldValue));
+            fields.Add(TRecordFieldLiteral.Create(TAst.Keyword(fieldName), fieldValue));
         end;
 
         Result := TAst.RecordLiteral(fields.ToArray);
@@ -945,7 +945,7 @@ var
     arg: IAstNode;
 begin
     // Special case for (quote ...) to print it as '...
-    if (Node.Callee is TIdentifierNode) and (TIdentifierNode(Node.Callee).Name = 'quote') and (Length(Node.Arguments) = 1) then
+    if (Node.Callee.Kind = akIdentifier) and (Node.Callee.AsIdentifier.Name = 'quote') and (Length(Node.Arguments) = 1) then
     begin
         Append('''');
         Node.Arguments[0].Accept(Self);

Src/AST/Myc.Ast.TypeChecker.pas

@@ -87,28 +87,19 @@ begin
 end;
 
 function TTypeChecker.VisitConstant(const Node: IConstantNode): IAstNode;
-var
-    constType: IStaticType;
 begin
     // This is a leaf node.
-    // Assign the type based on the literal value
-    case Node.Value.Kind of
-        TDataValueKind.vkScalar: constType := TTypes.FromScalarKind(Node.Value.AsScalar.Kind);
-        TDataValueKind.vkText: constType := TTypes.Text;
-        TDataValueKind.vkVoid: constType := TTypes.Void;
-    else
-        constType := TTypes.Unknown;
-    end;
-
-    // Create a new node with the correct type
-    Result := TConstantNode.Create(Node.Value, constType);
+    // If the constructor couldn't set the type, nobody can
+    Assert(Node.StaticType.Kind <> stUnknown);
+    Result := Node;
 end;
 
 function TTypeChecker.VisitKeyword(const Node: IKeywordNode): IAstNode;
 begin
     // This is a leaf node.
     // The TKeywordNode constructor *forces* the type to be TTypes.Keyword.
-    Result := TKeywordNode.Create(Node.Value);
+    Assert(Node.StaticType.Kind = stKeyword);
+    Result := Node;
 end;
 
 function TTypeChecker.VisitIdentifier(const Node: IIdentifierNode): IAstNode;
@@ -123,7 +114,7 @@ begin
     adr := Node.AsBoundIdentifierNode.Address;
 
     // Create a new node, copying the address and assigning the inferred type
-    Result := TBoundIdentifierNode.Create(Node.Name, adr, symbol.StaticType);
+    Result := TAst.BoundIdentifier(Node.Name, adr, symbol.StaticType);
 end;
 
 function TTypeChecker.VisitRecurNode(const Node: IRecurNode): IAstNode;
@@ -169,7 +160,7 @@ begin
         FCurrentDescriptor.UpdateType(adr.SlotIndex, initType);
 
     // 5. Create the new (typed) identifier node
-    newIdent := TBoundIdentifierNode.Create(boundIdent.Name, adr, initType);
+    newIdent := TAst.BoundIdentifier(boundIdent.Name, adr, initType);
 
     // 6. Create the new VariableDeclaration node
     Result := TVariableDeclarationNode.Create(newIdent.AsIdentifier, newInitializer, initType);
@@ -205,7 +196,7 @@ begin
         FCurrentDescriptor.UpdateType(adr.SlotIndex, sourceType);
 
         // Re-create the identifier node *with the new type*
-        newIdent := TBoundIdentifierNode.Create(newIdent.AsIdentifier.Name, adr, sourceType);
+        newIdent := TAst.BoundIdentifier(newIdent.AsIdentifier.Name, adr, sourceType);
         targetType := sourceType;
     end;
 
@@ -239,7 +230,7 @@ begin
             // (even if they are just TTypes.Unknown for now, for type inference placeholders)
             var paramIdent := boundNode.Parameters[i];
             var paramAdr := paramIdent.AsBoundIdentifierNode.Address;
-            var newParam := TBoundIdentifierNode.Create(paramIdent.Name, paramAdr, TTypes.Unknown);
+            var newParam := TAst.BoundIdentifier(paramIdent.Name, paramAdr);
 
             newParams[i] := newParam;
             paramTypes[i] := TTypes.Unknown;

Src/AST/Myc.Ast.Visitor.pas

@@ -571,28 +571,15 @@ end;
 
 function TAstTransformer.VisitMacroExpansionNode(const Node: IMacroExpansionNode): IAstNode;
 var
-    newBody: IAstNode;
-    N: TMacroExpansionNode;
-    newType: IStaticType;
+    newBody: IAstTypedNode;
 begin
-    N := (Node as TMacroExpansionNode);
+    // Visit the body and check if it changed
+    newBody := Accept(Node.ExpandedBody).AsTypedNode;
+    if newBody = Node.ExpandedBody then
+        exit(Node);
 
-    // 1. Visit the body
-    newBody := Accept(N.ExpandedBody);
-
-    // 2. Check if the body changed (Copy-on-Write)
-    if newBody = N.ExpandedBody then
-    begin
-        // No change, return the original immutable node
-        Result := Node;
-    end
-    else
-    begin
-        // The body changed. Create a NEW wrapper node.
-        // The type of the wrapper is the type of its body.
-        newType := newBody.AsTypedNode.StaticType;
-        Result := TMacroExpansionNode.Create(N.CallNode, newBody, newType);
-    end;
+    // The body changed. Create a NEW wrapper node.
+    Result := TMacroExpansionNode.Create(Node.CallNode, newBody);
 end;
 
 function TAstTransformer.VisitBlockExpression(const Node: IBlockExpressionNode): IAstNode;

Src/AST/Myc.Ast.pas

@@ -33,7 +33,7 @@ type
         class function Nop: IAstNode; static;
 
         // --- Factory functions ---
-        class function Constant(const AValue: TDataValue): IConstantNode; overload; static;
+        class function Constant(const AValue: TDataValue; const AStaticType: IStaticType = nil): IConstantNode; overload; static;
         class function Constant(const AValue: String): IConstantNode; overload; static;
         class function Keyword(const AName: string): IKeywordNode; static;
         class function Identifier(AName: string): IIdentifierNode; static;
@@ -71,13 +71,18 @@ type
         ): IAddSeriesItemNode; static;
         class function SeriesLength(const ASeries: IIdentifierNode): ISeriesLengthNode; static;
 
-        class function BoundIdentifier(AName: string; const Address: TResolvedAddress): IBoundIdentifierNode; static;
+        class function BoundIdentifier(
+            AName: string;
+            const Address: TResolvedAddress;
+            const AStaticType: IStaticType = nil
+        ): IBoundIdentifierNode; static;
     end;
 
     // Common base class for AST nodes to reduce boilerplate.
     TAstNode = class(TInterfacedObject, IAstNode)
     private
         function GetKind: TAstNodeKind; virtual; abstract;
+        function GetIsTyped: Boolean; virtual;
     public
         constructor Create;
         function Accept(const Visitor: IAstVisitor): TDataValue; virtual; abstract;
@@ -112,6 +117,7 @@ type
         function AsBoundIdentifierNode: IBoundIdentifierNode; virtual;
         function AsTypedNode: IAstTypedNode; virtual;
 
+        property IsTyped: Boolean read GetIsTyped;
         property Kind: TAstNodeKind read GetKind;
     end;
 
@@ -119,59 +125,13 @@ type
     private
         FStaticType: IStaticType;
         function GetStaticType: IStaticType;
+        function GetIsTyped: Boolean; override;
     public
         constructor Create(const AStaticType: IStaticType);
         function AsTypedNode: IAstTypedNode; override;
         property StaticType: IStaticType read GetStaticType;
     end;
 
-    TConstantNode = class(TAstTypedNode, IConstantNode)
-    private
-        FValue: TDataValue;
-        function GetValue: TDataValue;
-        function GetKind: TAstNodeKind; override;
-    public
-        constructor Create(const AValue: TDataValue; const AStaticType: IStaticType);
-        function Accept(const Visitor: IAstVisitor): TDataValue; override;
-        function AsConstant: IConstantNode; override;
-        property Value: TDataValue read GetValue; // Value ist immutable
-    end;
-
-    TIdentifierNode = class(TAstTypedNode, IIdentifierNode)
-    private
-        FName: string;
-        function GetName: string;
-        function GetKind: TAstNodeKind; override;
-    public
-        constructor Create(const AName: string; const AStaticType: IStaticType);
-        function Accept(const Visitor: IAstVisitor): TDataValue; override;
-        function AsIdentifier: IIdentifierNode; override;
-        property Name: string read FName; // Name ist immutable
-    end;
-
-    TBoundIdentifierNode = class(TIdentifierNode, IBoundIdentifierNode)
-    private
-        FAddress: TResolvedAddress;
-        function GetAddress: TResolvedAddress;
-        function GetKind: TAstNodeKind; override;
-    public
-        constructor Create(const AName: string; const AAddress: TResolvedAddress; const AStaticType: IStaticType);
-        function AsBoundIdentifierNode: IBoundIdentifierNode; override;
-        property Address: TResolvedAddress read GetAddress;
-    end;
-
-    TKeywordNode = class(TAstTypedNode, IKeywordNode)
-    private
-        FValue: IKeyword;
-        function GetValue: IKeyword;
-        function GetKind: TAstNodeKind; override;
-    public
-        constructor Create(const AValue: IKeyword);
-        function Accept(const Visitor: IAstVisitor): TDataValue; override;
-        function AsKeyword: IKeywordNode; override;
-        property Value: IKeyword read FValue; // Value ist immutable
-    end;
-
     TBinaryExpressionNode = class(TAstTypedNode, IBinaryExpressionNode)
     private
         FLeft: IAstNode;
@@ -263,60 +223,6 @@ type
         property HasNestedLambdas: Boolean read FHasNestedLambdas write FHasNestedLambdas;
     end;
 
-    TMacroDefinitionNode = class(TAstNode, IMacroDefinitionNode)
-    private
-        FName: IIdentifierNode;
-        FParameters: TArray<IIdentifierNode>;
-        FBody: IAstNode;
-        function GetName: IIdentifierNode;
-        function GetParameters: TArray<IIdentifierNode>;
-        function GetBody: IAstNode;
-        function GetKind: TAstNodeKind; override;
-    public
-        constructor Create(const AName: IIdentifierNode; const AParameters: TArray<IIdentifierNode>; const ABody: IAstNode);
-        function Accept(const Visitor: IAstVisitor): TDataValue; override;
-        function AsMacroDefinition: IMacroDefinitionNode; override;
-        property Name: IIdentifierNode read GetName;
-        property Parameters: TArray<IIdentifierNode> read FParameters;
-        property Body: IAstNode read FBody;
-    end;
-
-    TQuasiquoteNode = class(TAstNode, IQuasiquoteNode)
-    private
-        FExpression: IAstNode;
-        function GetExpression: IAstNode;
-        function GetKind: TAstNodeKind; override;
-    public
-        constructor Create(const AExpression: IAstNode);
-        function Accept(const Visitor: IAstVisitor): TDataValue; override;
-        function AsQuasiquote: IQuasiquoteNode; override;
-        property Expression: IAstNode read GetExpression;
-    end;
-
-    TUnquoteNode = class(TAstNode, IUnquoteNode)
-    private
-        FExpression: IAstNode;
-        function GetExpression: IAstNode;
-        function GetKind: TAstNodeKind; override;
-    public
-        constructor Create(const AExpression: IAstNode);
-        function Accept(const Visitor: IAstVisitor): TDataValue; override;
-        function AsUnquote: IUnquoteNode; override;
-        property Expression: IAstNode read GetExpression;
-    end;
-
-    TUnquoteSplicingNode = class(TAstNode, IUnquoteSplicingNode)
-    private
-        FExpression: IQuasiquoteNode;
-        function GetExpression: IQuasiquoteNode;
-        function GetKind: TAstNodeKind; override;
-    public
-        constructor Create(const AExpression: IQuasiquoteNode);
-        function Accept(const Visitor: IAstVisitor): TDataValue; override;
-        function AsUnquoteSplicing: IUnquoteSplicingNode; override;
-        property Expression: IQuasiquoteNode read GetExpression;
-    end;
-
     TFunctionCallNode = class(TAstTypedNode, IFunctionCallNode)
     private
         FCallee: IAstNode;
@@ -349,16 +255,16 @@ type
     TMacroExpansionNode = class(TAstTypedNode, IMacroExpansionNode)
     private
         FCallNode: IFunctionCallNode;
-        FExpandedBody: IAstNode;
+        FExpandedBody: IAstTypedNode;
         function GetCallNode: IFunctionCallNode;
         function GetExpandedBody: IAstNode;
         function GetKind: TAstNodeKind; override;
     public
-        constructor Create(const ACallNode: IFunctionCallNode; const AExpandedBody: IAstNode; const AStaticType: IStaticType);
+        constructor Create(const ACallNode: IFunctionCallNode; const AExpandedBody: IAstTypedNode);
         function Accept(const Visitor: IAstVisitor): TDataValue; override;
         function AsMacroExpansion: IMacroExpansionNode; override;
         property CallNode: IFunctionCallNode read GetCallNode;
-        property ExpandedBody: IAstNode read FExpandedBody;
+        property ExpandedBody: IAstTypedNode read FExpandedBody;
     end;
 
     TBlockExpressionNode = class(TAstTypedNode, IBlockExpressionNode)
@@ -508,8 +414,108 @@ implementation
 uses
     System.Generics.Defaults;
 
-// Added Nop
 type
+    TConstantNode = class(TAstTypedNode, IConstantNode)
+    private
+        FValue: TDataValue;
+        function GetValue: TDataValue;
+        function GetKind: TAstNodeKind; override;
+    public
+        constructor Create(const AValue: TDataValue; const AStaticType: IStaticType);
+        function Accept(const Visitor: IAstVisitor): TDataValue; override;
+        function AsConstant: IConstantNode; override;
+        property Value: TDataValue read GetValue;
+    end;
+
+    TIdentifierNode = class(TAstTypedNode, IIdentifierNode)
+    private
+        FName: string;
+        function GetName: string;
+        function GetKind: TAstNodeKind; override;
+    public
+        constructor Create(const AName: string; const AStaticType: IStaticType);
+        function Accept(const Visitor: IAstVisitor): TDataValue; override;
+        function AsIdentifier: IIdentifierNode; override;
+        property Name: string read FName;
+    end;
+
+    TBoundIdentifierNode = class(TIdentifierNode, IBoundIdentifierNode)
+    private
+        FAddress: TResolvedAddress;
+        function GetAddress: TResolvedAddress;
+        function GetKind: TAstNodeKind; override;
+    public
+        constructor Create(const AName: string; const AAddress: TResolvedAddress; const AStaticType: IStaticType);
+        function AsBoundIdentifierNode: IBoundIdentifierNode; override;
+        property Address: TResolvedAddress read GetAddress;
+    end;
+
+    TKeywordNode = class(TAstTypedNode, IKeywordNode)
+    private
+        FValue: IKeyword;
+        function GetValue: IKeyword;
+        function GetKind: TAstNodeKind; override;
+    public
+        constructor Create(const AValue: IKeyword);
+        function Accept(const Visitor: IAstVisitor): TDataValue; override;
+        function AsKeyword: IKeywordNode; override;
+        property Value: IKeyword read FValue; // Value ist immutable
+    end;
+
+    TMacroDefinitionNode = class(TAstNode, IMacroDefinitionNode)
+    private
+        FName: IIdentifierNode;
+        FParameters: TArray<IIdentifierNode>;
+        FBody: IAstNode;
+        function GetName: IIdentifierNode;
+        function GetParameters: TArray<IIdentifierNode>;
+        function GetBody: IAstNode;
+        function GetKind: TAstNodeKind; override;
+    public
+        constructor Create(const AName: IIdentifierNode; const AParameters: TArray<IIdentifierNode>; const ABody: IAstNode);
+        function Accept(const Visitor: IAstVisitor): TDataValue; override;
+        function AsMacroDefinition: IMacroDefinitionNode; override;
+        property Name: IIdentifierNode read GetName;
+        property Parameters: TArray<IIdentifierNode> read FParameters;
+        property Body: IAstNode read FBody;
+    end;
+
+    TQuasiquoteNode = class(TAstNode, IQuasiquoteNode)
+    private
+        FExpression: IAstNode;
+        function GetExpression: IAstNode;
+        function GetKind: TAstNodeKind; override;
+    public
+        constructor Create(const AExpression: IAstNode);
+        function Accept(const Visitor: IAstVisitor): TDataValue; override;
+        function AsQuasiquote: IQuasiquoteNode; override;
+        property Expression: IAstNode read GetExpression;
+    end;
+
+    TUnquoteNode = class(TAstNode, IUnquoteNode)
+    private
+        FExpression: IAstNode;
+        function GetExpression: IAstNode;
+        function GetKind: TAstNodeKind; override;
+    public
+        constructor Create(const AExpression: IAstNode);
+        function Accept(const Visitor: IAstVisitor): TDataValue; override;
+        function AsUnquote: IUnquoteNode; override;
+        property Expression: IAstNode read GetExpression;
+    end;
+
+    TUnquoteSplicingNode = class(TAstNode, IUnquoteSplicingNode)
+    private
+        FExpression: IQuasiquoteNode;
+        function GetExpression: IQuasiquoteNode;
+        function GetKind: TAstNodeKind; override;
+    public
+        constructor Create(const AExpression: IQuasiquoteNode);
+        function Accept(const Visitor: IAstVisitor): TDataValue; override;
+        function AsUnquoteSplicing: IUnquoteSplicingNode; override;
+        property Expression: IQuasiquoteNode read GetExpression;
+    end;
+
     TNopNode = class(TAstNode, INopNode)
     private
         function GetKind: TAstNodeKind; override;
@@ -574,14 +580,28 @@ begin
     Result := TBlockExpressionNode.Create(AExpressions, TTypes.Unknown);
 end;
 
-class function TAst.Constant(const AValue: TDataValue): IConstantNode;
+class function TAst.Constant(const AValue: TDataValue; const AStaticType: IStaticType = nil): IConstantNode;
 begin
-    Result := TConstantNode.Create(AValue, TTypes.Unknown);
+    var constType := AStaticType;
+
+    if constType = nil then
+    begin
+        case AValue.Kind of
+            TDataValueKind.vkScalar: constType := TTypes.FromScalarKind(AValue.AsScalar.Kind);
+            TDataValueKind.vkText: constType := TTypes.Text;
+            TDataValueKind.vkVoid: constType := TTypes.Void;
+        else
+            constType := TTypes.Unknown;
+        end;
+    end;
+
+    // Create a new node with the correct type
+    Result := TConstantNode.Create(AValue, constType);
 end;
 
 class function TAst.Constant(const AValue: String): IConstantNode;
 begin
-    Result := TConstantNode.Create(AValue, TTypes.Unknown);
+    Result := TConstantNode.Create(AValue, TTypes.Text);
 end;
 
 class constructor TAst.Create;
@@ -594,9 +614,19 @@ begin
     FLibraries.Free;
 end;
 
-class function TAst.BoundIdentifier(AName: string; const Address: TResolvedAddress): IBoundIdentifierNode;
+class function TAst.BoundIdentifier(
+    AName: string;
+    const Address: TResolvedAddress;
+    const AStaticType: IStaticType = nil
+): IBoundIdentifierNode;
 begin
-    Result := TBoundIdentifierNode.Create(AName, Address, TTypes.Unknown);
+    Result :=
+        TBoundIdentifierNode.Create(
+            AName,
+            Address,
+            if AStaticType <> nil then AStaticType
+            else TTypes.Unknown
+        );
 end;
 
 class procedure TAst.RegisterLibrary(const AProc: TRegisterLibraryProc);
@@ -645,7 +675,10 @@ end;
 
 class function TAst.MacroExpansionNode(const AOriginalCallNode: IFunctionCallNode; const AExpandedBody: IAstNode): IMacroExpansionNode;
 begin
-    Result := TMacroExpansionNode.Create(AOriginalCallNode, AExpandedBody, TTypes.Unknown);
+    if AExpandedBody.IsTyped then
+        Result := TMacroExpansionNode.Create(AOriginalCallNode, AExpandedBody.AsTypedNode)
+    else
+        Result := TMacroExpansionNode.Create(AOriginalCallNode, Block([]));
 end;
 
 class function TAst.MemberAccess(const ABase: IAstNode; const AMember: IKeywordNode): IMemberAccessNode;
@@ -871,6 +904,11 @@ begin
     raise ETypeException.Create('Node is not a VariableDeclaration');
 end;
 
+function TAstNode.GetIsTyped: Boolean;
+begin
+    Result := false;
+end;
+
 { TAstTypedNode }
 
 constructor TAstTypedNode.Create(const AStaticType: IStaticType);
@@ -885,6 +923,11 @@ begin
     Result := Self;
 end;
 
+function TAstTypedNode.GetIsTyped: Boolean;
+begin
+    Result := true;
+end;
+
 function TAstTypedNode.GetStaticType: IStaticType;
 begin
     Result := FStaticType;
@@ -1334,10 +1377,10 @@ end;
 
 { TMacroExpansionNode }
 
-constructor TMacroExpansionNode.Create(const ACallNode: IFunctionCallNode; const AExpandedBody: IAstNode; const AStaticType: IStaticType);
+constructor TMacroExpansionNode.Create(const ACallNode: IFunctionCallNode; const AExpandedBody: IAstTypedNode);
 begin
     // Copy properties from the original call node
-    inherited Create(AStaticType);
+    inherited Create(AExpandedBody.StaticType);
     FExpandedBody := AExpandedBody;
     FCallNode := ACallNode;
 end;