Refactoring + Panning in Workspace

ASTPlayground/Myc.Ast.Visualizer.pas

@@ -7,6 +7,7 @@ uses
     System.Classes,
     System.UITypes,
     System.Types,
+    System.Math.Vectors,
     System.Generics.Collections,
     FMX.Types,
     FMX.Controls,
@@ -114,11 +115,26 @@ type
     TAuraWorkspace = class(TStyledControl)
     private
         FConnections: TArray<TPinConnection>;
+        // If the mouse is dragging the background (i.e., no child control is being dragged),
+        // then FPanning should be dragged.
+        FPanning: TSizeF;
+        // Added for panning implementation.
+        FIsPanning: Boolean;
+        FLastPanPos: TPointF;
+        // Added for zooming implementation.
+        FZoom: Single;
     protected
         procedure Paint; override;
         procedure DoDeleteChildren; override;
+        // Add a zoom factor that, along with FPanning, zooms the children via the mouse wheel.
+        procedure MouseDown(Button: TMouseButton; Shift: TShiftState; X, Y: Single); override;
+        procedure MouseMove(Shift: TShiftState; X, Y: Single); override;
+        procedure MouseUp(Button: TMouseButton; Shift: TShiftState; X, Y: Single); override;
+        procedure MouseWheel(Shift: TShiftState; WheelDelta: Integer; var Handled: Boolean); override;
     public
+        constructor Create(AOwner: TComponent); override;
         procedure BuildTree(const Root: IAstNode; const Position: TPointF; AMode: TVisualizationMode);
+        function GetChildrenMatrix(var Matrix: TMatrix; var Simple: Boolean): Boolean; override;
 
     published
         // Standard control properties
@@ -267,6 +283,7 @@ implementation
 uses
     System.Math,
     System.StrUtils,
+    FMX.Platform,
     Myc.Data.Scalar;
 
 type
@@ -303,34 +320,34 @@ begin
     lookbackStr := '';
     if Assigned(Node.Lookback) then
         lookbackStr := ', ' + Node.Lookback.Accept(Self).AsText;
-    Result := TAstValue.FromText(Format('%s.add(%s%s)', [seriesStr, valueStr, lookbackStr]));
+    Result := Format('%s.add(%s%s)', [seriesStr, valueStr, lookbackStr]);
 end;
 
 function TAstToTextVisitor.VisitAssignment(const Node: IAssignmentNode): TAstValue;
 begin
-    Result := TAstValue.FromText(Node.Identifier.Name + ' := ' + Node.Value.Accept(Self).AsText);
+    Result := Node.Identifier.Name + ' := ' + Node.Value.Accept(Self).AsText;
 end;
 
 function TAstToTextVisitor.VisitBinaryExpression(const Node: IBinaryExpressionNode): TAstValue;
 begin
     var leftStr := Node.Left.Accept(Self).AsText;
     var rightStr := Node.Right.Accept(Self).AsText;
-    Result := TAstValue.FromText('(' + leftStr + ' ' + Node.Operator.ToString + ' ' + rightStr + ')');
+    Result := '(' + leftStr + ' ' + Node.Operator.ToString + ' ' + rightStr + ')';
 end;
 
 function TAstToTextVisitor.VisitBlockExpression(const Node: IBlockExpressionNode): TAstValue;
 begin
-    Result := TAstValue.FromText('{...}');
+    Result := '{...}';
 end;
 
 function TAstToTextVisitor.VisitConstant(const Node: IConstantNode): TAstValue;
 begin
-    Result := TAstValue.FromText(Node.Value.ToString);
+    Result := Node.Value.ToString;
 end;
 
 function TAstToTextVisitor.VisitCreateSeries(const Node: ICreateSeriesNode): TAstValue;
 begin
-    Result := TAstValue.FromText('new series(' + Node.Definition + ')');
+    Result := 'new series(' + Node.Definition + ')';
 end;
 
 function TAstToTextVisitor.VisitFunctionCall(const Node: IFunctionCallNode): TAstValue;
@@ -352,7 +369,7 @@ begin
                 sb.Append(', ');
         end;
         sb.Append(')');
-        Result := TAstValue.FromText(sb.ToString);
+        Result := sb.ToString;
     finally
         sb.Free;
     end;
@@ -360,12 +377,12 @@ end;
 
 function TAstToTextVisitor.VisitIdentifier(const Node: IIdentifierNode): TAstValue;
 begin
-    Result := TAstValue.FromText(Node.Name);
+    Result := Node.Name;
 end;
 
 function TAstToTextVisitor.VisitIfExpression(const Node: IIfExpressionNode): TAstValue;
 begin
-    Result := TAstValue.FromText(Node.Condition.Accept(Self).AsText);
+    Result := Node.Condition.Accept(Self).AsText;
 end;
 
 function TAstToTextVisitor.VisitIndexer(const Node: IIndexerNode): TAstValue;
@@ -374,7 +391,7 @@ var
 begin
     baseStr := Node.Base.Accept(Self).AsText;
     indexStr := Node.Index.Accept(Self).AsText;
-    Result := TAstValue.FromText(Format('%s[%s]', [baseStr, indexStr]));
+    Result := Format('%s[%s]', [baseStr, indexStr]);
 end;
 
 function TAstToTextVisitor.VisitLambdaExpression(const Node: ILambdaExpressionNode): TAstValue;
@@ -396,7 +413,7 @@ begin
             end;
         end;
         sb.Append(') => {...}');
-        Result := TAstValue.FromText(sb.ToString);
+        Result := sb.ToString;
     finally
         sb.Free;
     end;
@@ -407,7 +424,7 @@ var
     baseStr: string;
 begin
     baseStr := Node.Base.Accept(Self).AsText;
-    Result := TAstValue.FromText(Format('%s.%s', [baseStr, Node.Member.Name]));
+    Result := Format('%s.%s', [baseStr, Node.Member.Name]);
 end;
 
 function TAstToTextVisitor.VisitSeriesLength(const Node: ISeriesLengthNode): TAstValue;
@@ -416,7 +433,7 @@ var
 begin
     // Get the string representation of the series identifier by visiting the node.
     seriesStr := Node.Series.Accept(Self).AsText;
-    Result := TAstValue.FromText(Format('length(%s)', [seriesStr]));
+    Result := Format('length(%s)', [seriesStr]);
 end;
 
 function TAstToTextVisitor.VisitTernaryExpression(const Node: ITernaryExpressionNode): TAstValue;
@@ -424,12 +441,12 @@ begin
     var condStr := Node.Condition.Accept(Self).AsText;
     var thenStr := Node.ThenBranch.Accept(Self).AsText;
     var elseStr := Node.ElseBranch.Accept(Self).AsText;
-    Result := TAstValue.FromText(Format('(%s ? %s : %s)', [condStr, thenStr, elseStr]));
+    Result := Format('(%s ? %s : %s)', [condStr, thenStr, elseStr]);
 end;
 
 function TAstToTextVisitor.VisitUnaryExpression(const Node: IUnaryExpressionNode): TAstValue;
 begin
-    Result := TAstValue.FromText(Node.Operator.ToString + ' ' + Node.Right.Accept(Self).AsText);
+    Result := Node.Operator.ToString + ' ' + Node.Right.Accept(Self).AsText;
 end;
 
 function TAstToTextVisitor.VisitVariableDeclaration(const Node: IVariableDeclarationNode): TAstValue;
@@ -440,7 +457,7 @@ begin
         initStr := ' := ' + Node.Initializer.Accept(Self).AsText
     else
         initStr := '';
-    Result := TAstValue.FromText('var ' + Node.Identifier.Name + initStr);
+    Result := 'var ' + Node.Identifier.Name + initStr;
 end;
 
 { TPinConnection }
@@ -479,7 +496,7 @@ begin
     Height := 45;
 
     // The panel must be able to receive mouse events.
-    HitTest := True;
+    //    HitTest := True;
     // Clip children to the panel's bounds.
     ClipChildren := True;
 end;
@@ -619,6 +636,7 @@ begin
         begin
             FIsDragging := True;
             FDownPos := TPointF.Create(X, Y);
+            Capture;
         end;
     end;
 end;
@@ -626,6 +644,7 @@ end;
 procedure TAuraNode.MouseMove(Shift: TShiftState; X, Y: Single);
 begin
     inherited;
+
     if FIsDragging then
     begin
         var deltaX := X - FDownPos.X;
@@ -644,12 +663,20 @@ begin
     inherited;
     if (Button = TMouseButton.mbLeft) and (FIsDragging) then
     begin
+        ReleaseCapture;
         FIsDragging := False;
     end;
 end;
 
 { TAuraWorkspace }
 
+constructor TAuraWorkspace.Create(AOwner: TComponent);
+begin
+    inherited;
+    // Initialize zoom factor.
+    FZoom := 1.0;
+end;
+
 procedure TAuraWorkspace.BuildTree(const Root: IAstNode; const Position: TPointF; AMode: TVisualizationMode);
 begin
     var connections := TList<TPinConnection>.Create;
@@ -667,6 +694,97 @@ begin
     inherited;
 end;
 
+function TAuraWorkspace.GetChildrenMatrix(var Matrix: TMatrix; var Simple: Boolean): Boolean;
+begin
+    // Combine scaling (zoom) and translation (pan) into a single matrix.
+    // The order is important: scale first, then translate.
+    Matrix := TMatrix.CreateScaling(FZoom, FZoom) * TMatrix.CreateTranslation(FPanning.cx, FPanning.cy);
+    Simple := (FZoom = 1.0) and (FPanning.cx = 0) and (FPanning.cy = 0);
+    Result := true;
+end;
+
+procedure TAuraWorkspace.MouseDown(Button: TMouseButton; Shift: TShiftState; X, Y: Single);
+begin
+    inherited;
+    // Start panning if left button is pressed on the background
+    if (Button = TMouseButton.mbLeft) and (ObjectAtPoint(LocalToScreen(TPointF.Create(X, Y))) = Self as IControl) then
+    begin
+        FIsPanning := True;
+        FLastPanPos := TPointF.Create(X, Y);
+        Cursor := crHandPoint;
+    end;
+end;
+
+procedure TAuraWorkspace.MouseMove(Shift: TShiftState; X, Y: Single);
+var
+    delta: TPointF;
+begin
+    inherited;
+
+    if FIsPanning then
+    begin
+        // Calculate movement delta
+        delta := TPointF.Create(X - FLastPanPos.X, Y - FLastPanPos.Y);
+
+        // Update panning offset
+        FPanning.cx := FPanning.cx + delta.X;
+        FPanning.cy := FPanning.cy + delta.Y;
+
+        // Store current position for next move
+        FLastPanPos := TPointF.Create(X, Y);
+
+        // Trigger repaint to apply the new transformation matrix
+        RecalcAbsolute;
+        RecalcUpdateRect;
+        Repaint;
+    end;
+end;
+
+procedure TAuraWorkspace.MouseUp(Button: TMouseButton; Shift: TShiftState; X, Y: Single);
+begin
+    inherited;
+    // Stop panning
+    if (Button = TMouseButton.mbLeft) and (FIsPanning) then
+    begin
+        FIsPanning := False;
+        Cursor := crDefault;
+    end;
+end;
+
+procedure TAuraWorkspace.MouseWheel(Shift: TShiftState; WheelDelta: Integer; var Handled: Boolean);
+var
+    oldZoom: Single;
+    MouseService: IFMXMouseService;
+begin
+    inherited;
+
+    if TPlatformServices.Current.SupportsPlatformService(IFMXMouseService, MouseService) then
+    begin
+        var MousePos := ScreenToLocal(MouseService.GetMousePos);
+
+        oldZoom := FZoom;
+
+        // Calculate new zoom
+        if WheelDelta > 0 then
+            FZoom := FZoom * 1.1
+        else
+            FZoom := FZoom / 1.1;
+
+        // Clamp zoom level to a reasonable range
+        FZoom := Max(0.2, Min(3.0, FZoom));
+
+        // Adjust panning to keep the point under the cursor stationary
+        FPanning.cx := MousePos.X * (1 - FZoom / oldZoom) + FPanning.cx * (FZoom / oldZoom);
+        FPanning.cy := MousePos.Y * (1 - FZoom / oldZoom) + FPanning.cy * (FZoom / oldZoom);
+
+        // Trigger repaint to apply the new transformation matrix
+        RecalcAbsolute;
+        RecalcUpdateRect;
+        Repaint;
+        Handled := True;
+    end;
+end;
+
 procedure TAuraWorkspace.Paint;
 var
     connection: TPinConnection;

Src/AST/Myc.Ast.Evaluator.pas

@@ -122,61 +122,6 @@ type
         property Method: TNativeFunction read FMethod;
     end;
 
-// --- Helper Functions ---
-
-function ScalarKindToString(AKind: TScalarKind): string;
-begin
-    case AKind of
-        skInteger: Result := 'integer';
-        skInt64: Result := 'int64';
-        skUInt64: Result := 'uint64';
-        skSingle: Result := 'single';
-        skDouble: Result := 'double';
-        skDateTime: Result := 'datetime';
-        skTimestamp: Result := 'timestamp';
-        skBoolean: Result := 'boolean';
-        skChar: Result := 'char';
-        skPChar: Result := 'pchar';
-        skString: Result := 'string';
-        skBytes: Result := 'bytes';
-        skDecimal: Result := 'decimal';
-    else
-        Result := 'unknown';
-    end;
-end;
-
-function StringToScalarKind(const AName: string): TScalarKind;
-begin
-    if SameText(AName, 'integer') then
-        Result := skInteger
-    else if SameText(AName, 'int64') then
-        Result := skInt64
-    else if SameText(AName, 'uint64') then
-        Result := skUInt64
-    else if SameText(AName, 'single') then
-        Result := skSingle
-    else if SameText(AName, 'double') then
-        Result := skDouble
-    else if SameText(AName, 'datetime') then
-        Result := skDateTime
-    else if SameText(AName, 'timestamp') then
-        Result := skTimestamp
-    else if SameText(AName, 'boolean') then
-        Result := skBoolean
-    else if SameText(AName, 'char') then
-        Result := skChar
-    else if SameText(AName, 'pchar') then
-        Result := skPChar
-    else if SameText(AName, 'string') then
-        Result := skString
-    else if SameText(AName, 'bytes') then
-        Result := skBytes
-    else if SameText(AName, 'decimal') then
-        Result := skDecimal
-    else
-        raise EArgumentException.CreateFmt('Unknown scalar type name: "%s"', [AName]);
-end;
-
 // --- Native Functions Implementation ---
 
 function NativeCreateRecordSeries(const Args: TArray<TAstValue>): TAstValue;
@@ -201,13 +146,10 @@ end;
 // --- Registration Procedure ---
 
 procedure RegisterNativeFunctions(const AScope: IExecutionScope);
-var
-    closure: TAstValue.IClosure;
 begin
     // Use 'Define' to clearly state that we are adding a new variable
     // to the global scope before the binder runs.
-    closure := TNativeClosure.Create(NativeCreateRecordSeries);
+    AScope.Define('CreateRecordSeries', TNativeClosure.Create(NativeCreateRecordSeries));
-    AScope.Define('CreateRecordSeries', TAstValue.FromClosure(closure));
 end;
 
 { TClosureValue }
@@ -335,9 +277,8 @@ begin
             with seriesVar.AsSeries.Value do
             begin
                 if (itemValue.AsScalar.Kind <> Kind) then
-                    raise EArgumentException.CreateFmt(
+                    raise EArgumentException
-                        'Type mismatch: Cannot add %s to a series of %s.',
+                        .CreateFmt('Type mismatch: Cannot add %s to a series of %s.', [itemValue.AsScalar.Kind.ToString, Kind.ToString]);
-                        [ScalarKindToString(itemValue.AsScalar.Kind), ScalarKindToString(Kind)]);
 
                 Items.Add(itemValue.AsScalar.Value, lookback);
             end;
@@ -365,7 +306,7 @@ end;
 
 function TEvaluatorVisitor.VisitConstant(const Node: IConstantNode): TAstValue;
 begin
-    Result := TAstValue.FromScalar(Node.Value);
+    Result := Node.Value;
 end;
 
 function TEvaluatorVisitor.VisitCreateSeries(const Node: ICreateSeriesNode): TAstValue;
@@ -385,7 +326,7 @@ begin
     end
     else
     begin
-        var scalarKind := StringToScalarKind(def);
+        var scalarKind := TScalar.StringToKind(def);
         var scalarSeries := TScalarSeries.Create(scalarKind, Default(TSeries<TScalarValue>));
         Result := TAstValue.FromSeries(scalarSeries);
     end;
@@ -424,7 +365,7 @@ begin
                 if (index < 0) or (index >= Items.TotalCount) then
                     raise EArgumentException.CreateFmt('Index %d is out of bounds for series with %d elements.', [index, Items.TotalCount]);
 
-                Result := TAstValue.FromScalar(TScalar.Create(Kind, Items[Integer(index)]));
+                Result := TScalar.Create(Kind, Items[Integer(index)]);
             end;
         end;
         avkRecordSeries:
@@ -443,8 +384,7 @@ begin
                 raise EArgumentException
                     .CreateFmt('Index %d is out of bounds for member series with %d elements.', [index, memberSeries.Count]);
 
-            var scalarValue := memberSeries.Items[Integer(index)];
+            Result := memberSeries.Items[Integer(index)];
-            Result := TAstValue.FromScalar(scalarValue);
         end;
     else
         raise EArgumentException.Create('Indexer `[]` is not supported for this value type.');
@@ -465,17 +405,17 @@ begin
             with baseValue.AsSeries.Value do
             begin
                 if SameText(memberName, 'Count') then
-                    Result := TAstValue.FromScalar(TScalar.FromInt64(Items.Count))
+                    Result := TScalar.FromInt64(Items.Count)
                 else if SameText(memberName, 'TotalCount') then
-                    Result := TAstValue.FromScalar(TScalar.FromInt64(Items.TotalCount))
+                    Result := TScalar.FromInt64(Items.TotalCount)
                 else if SameText(memberName, 'Kind') then
-                    Result := TAstValue.FromText(ScalarKindToString(Kind))
+                    Result := Kind.ToString
                 else
                     raise EArgumentException.CreateFmt('Member "%s" not found on TScalarSeries.', [memberName]);
             end;
         end;
         avkRecordSeries: Result := TAstValue.FromMemberSeries(baseValue.AsRecordSeries.Value.CreateMemberSeries(memberName));
-        avkRecord: Result := TAstValue.FromScalar(baseValue.AsRecord.Items[memberName]);
+        avkRecord: Result := baseValue.AsRecord.Items[memberName];
     else
         raise EArgumentException.Create('Member access operator `.` is not supported for this value type.');
     end;
@@ -507,16 +447,9 @@ begin
     sourceAddresses := Node.Upvalues;
     SetLength(capturedCells, Length(sourceAddresses));
     for i := 0 to High(sourceAddresses) do
-    begin
+        capturedCells[i] := FScope.GetCell(sourceAddresses[i]);
-        sourceAddr := sourceAddresses[i];
-        // The binder gives the depth relative to the lambda's
-        // inner scope. The evaluator is in the outer scope, so we adjust the
-        // depth by -1 to find the cell in the current context.
-        dec(sourceAddr.ScopeDepth);
-        capturedCells[i] := FScope.GetCell(sourceAddr);
-    end;
 
-    Result := TAstValue.FromClosure(TClosureValue.Create(Node, FScope, capturedCells));
+    Result := TClosureValue.Create(Node, FScope, capturedCells);
 end;
 
 function TEvaluatorVisitor.VisitFunctionCall(const Node: IFunctionCallNode): TAstValue;
@@ -610,16 +543,16 @@ begin
             var leftVal := leftScalar.Value.AsInt64;
             var rightVal := rightScalar.Value.AsInt64;
             case Node.Operator of
-                boAdd: Result := TAstValue.FromScalar(TScalar.FromInt64(leftVal + rightVal));
+                boAdd: Result := TScalar.FromInt64(leftVal + rightVal);
-                boSubtract: Result := TAstValue.FromScalar(TScalar.FromInt64(leftVal - rightVal));
+                boSubtract: Result := TScalar.FromInt64(leftVal - rightVal);
-                boMultiply: Result := TAstValue.FromScalar(TScalar.FromInt64(leftVal * rightVal));
+                boMultiply: Result := TScalar.FromInt64(leftVal * rightVal);
-                boDivide: Result := TAstValue.FromScalar(TScalar.FromInt64(leftVal div rightVal));
+                boDivide: Result := TScalar.FromInt64(leftVal div rightVal);
-                boEqual: Result := TAstValue.FromScalar(TScalar.FromBoolean(leftVal = rightVal));
+                boEqual: Result := TScalar.FromBoolean(leftVal = rightVal);
-                boNotEqual: Result := TAstValue.FromScalar(TScalar.FromBoolean(leftVal <> rightVal));
+                boNotEqual: Result := TScalar.FromBoolean(leftVal <> rightVal);
-                boLess: Result := TAstValue.FromScalar(TScalar.FromBoolean(leftVal < rightVal));
+                boLess: Result := TScalar.FromBoolean(leftVal < rightVal);
-                boGreater: Result := TAstValue.FromScalar(TScalar.FromBoolean(leftVal > rightVal));
+                boGreater: Result := TScalar.FromBoolean(leftVal > rightVal);
-                boLessOrEqual: Result := TAstValue.FromScalar(TScalar.FromBoolean(leftVal <= rightVal));
+                boLessOrEqual: Result := TScalar.FromBoolean(leftVal <= rightVal);
-                boGreaterOrEqual: Result := TAstValue.FromScalar(TScalar.FromBoolean(leftVal >= rightVal));
+                boGreaterOrEqual: Result := TScalar.FromBoolean(leftVal >= rightVal);
             else
                 raise ENotSupportedException.Create('Operator not supported for Int64.');
             end;
@@ -629,16 +562,16 @@ begin
             var leftVal := leftScalar.Value.AsDouble;
             var rightVal := rightScalar.Value.AsDouble;
             case Node.Operator of
-                boAdd: Result := TAstValue.FromScalar(TScalar.FromDouble(leftVal + rightVal));
+                boAdd: Result := TScalar.FromDouble(leftVal + rightVal);
-                boSubtract: Result := TAstValue.FromScalar(TScalar.FromDouble(leftVal - rightVal));
+                boSubtract: Result := TScalar.FromDouble(leftVal - rightVal);
-                boMultiply: Result := TAstValue.FromScalar(TScalar.FromDouble(leftVal * rightVal));
+                boMultiply: Result := TScalar.FromDouble(leftVal * rightVal);
-                boDivide: Result := TAstValue.FromScalar(TScalar.FromDouble(leftVal / rightVal));
+                boDivide: Result := TScalar.FromDouble(leftVal / rightVal);
-                boEqual: Result := TAstValue.FromScalar(TScalar.FromBoolean(leftVal = rightVal));
+                boEqual: Result := TScalar.FromBoolean(leftVal = rightVal);
-                boNotEqual: Result := TAstValue.FromScalar(TScalar.FromBoolean(leftVal <> rightVal));
+                boNotEqual: Result := TScalar.FromBoolean(leftVal <> rightVal);
-                boLess: Result := TAstValue.FromScalar(TScalar.FromBoolean(leftVal < rightVal));
+                boLess: Result := TScalar.FromBoolean(leftVal < rightVal);
-                boGreater: Result := TAstValue.FromScalar(TScalar.FromBoolean(leftVal > rightVal));
+                boGreater: Result := TScalar.FromBoolean(leftVal > rightVal);
-                boLessOrEqual: Result := TAstValue.FromScalar(TScalar.FromBoolean(leftVal <= rightVal));
+                boLessOrEqual: Result := TScalar.FromBoolean(leftVal <= rightVal);
-                boGreaterOrEqual: Result := TAstValue.FromScalar(TScalar.FromBoolean(leftVal >= rightVal));
+                boGreaterOrEqual: Result := TScalar.FromBoolean(leftVal >= rightVal);
             else
                 raise ENotSupportedException.Create('Operator not supported for Double.');
             end;
@@ -662,15 +595,15 @@ begin
                 raise ENotSupportedException.Create('Unary "-" is only supported for scalar types.');
             rightScalar := rightValue.AsScalar;
             case rightScalar.Kind of
-                skInt64: Result := TAstValue.FromScalar(TScalar.FromInt64(-rightScalar.Value.AsInt64));
+                skInt64: Result := TScalar.FromInt64(-rightScalar.Value.AsInt64);
-                skDouble: Result := TAstValue.FromScalar(TScalar.FromDouble(-rightScalar.Value.AsDouble));
+                skDouble: Result := TScalar.FromDouble(-rightScalar.Value.AsDouble);
             else
                 raise ENotSupportedException.Create('Unary "-" is not supported for this scalar type.');
             end;
         end;
         uoNot:
         begin
-            Result := TAstValue.FromScalar(TScalar.FromBoolean(not IsTruthy(rightValue)));
+            Result := TScalar.FromBoolean(not IsTruthy(rightValue));
         end;
     else
         raise ENotSupportedException.Create('Unary operator not supported');
@@ -731,7 +664,7 @@ begin
         raise EArgumentException.CreateFmt('Cannot get length of type %s.', [GetEnumName(TypeInfo(TAstValueKind), Ord(seriesValue.Kind))]);
     end;
 
-    Result := TAstValue.FromScalar(TScalar.FromInt64(len));
+    Result := TScalar.FromInt64(len);
 end;
 
 { TDebugEvaluatorVisitor }

Src/AST/Myc.Ast.Nodes.pas

@@ -80,9 +80,9 @@ type
     public
         class operator Initialize(out Dest: TAstValue);
         class function Void: TAstValue; inline; static;
-        class function FromScalar(const AValue: TScalar): TAstValue; inline; static;
+        class operator Implicit(const AValue: TScalar): TAstValue; overload; inline;
-        class function FromClosure(const AValue: TAstValue.IClosure): TAstValue; inline; static;
+        class operator Implicit(const AValue: TAstValue.IClosure): TAstValue; overload; inline;
-        class function FromText(const AValue: String): TAstValue; inline; static;
+        class operator Implicit(const AValue: String): TAstValue; overload; inline;
         class function FromSeries(const [ref] AValue: TScalarSeries): TAstValue; static; inline;
         class function FromRecordSeries(const [ref] AValue: TScalarRecordSeries): TAstValue; static; inline;
         class function FromRecord(const [ref] AValue: TScalarRecord): TAstValue; static; inline;
@@ -116,8 +116,7 @@ type
         Kind: TAddressKind;
         ScopeDepth: Integer;
         SlotIndex: Integer;
-        Name: String;
+        constructor Create(AKind: TAddressKind; AScopeDepth, ASlotIndex: Integer);
-        constructor Create(AKind: TAddressKind; AScopeDepth, ASlotIndex: Integer; const AName: String);
         class operator Initialize(out Dest: TResolvedAddress);
     end;
 
@@ -402,7 +401,7 @@ begin
     Result := (FInterface as TVal<String>).Value;
 end;
 
-class function TAstValue.FromClosure(const AValue: TAstValue.IClosure): TAstValue;
+class operator TAstValue.Implicit(const AValue: TAstValue.IClosure): TAstValue;
 begin
     Result.FKind := avkClosure;
     Result.FInterface := AValue;
@@ -430,7 +429,7 @@ begin
     Result.FScalar := Default(TScalar);
 end;
 
-class function TAstValue.FromScalar(const AValue: TScalar): TAstValue;
+class operator TAstValue.Implicit(const AValue: TScalar): TAstValue;
 begin
     Result.FKind := avkScalar;
     Result.FScalar := AValue;
@@ -444,7 +443,7 @@ begin
     Result.FScalar := Default(TScalar);
 end;
 
-class function TAstValue.FromText(const AValue: String): TAstValue;
+class operator TAstValue.Implicit(const AValue: String): TAstValue;
 begin
     Result.FKind := avkText;
     Result.FInterface := TVal<String>.Create(AValue);
@@ -484,12 +483,11 @@ end;
 
 { TResolvedAddress }
 
-constructor TResolvedAddress.Create(AKind: TAddressKind; AScopeDepth, ASlotIndex: Integer; const AName: String);
+constructor TResolvedAddress.Create(AKind: TAddressKind; AScopeDepth, ASlotIndex: Integer);
 begin
     Kind := AKind;
     ScopeDepth := AScopeDepth;
     SlotIndex := ASlotIndex;
-    Name := AName;
 end;
 
 class operator TResolvedAddress.Initialize(out Dest: TResolvedAddress);
@@ -497,7 +495,6 @@ begin
     Dest.Kind := akUnresolved;
     Dest.ScopeDepth := -1;
     Dest.SlotIndex := -1;
-    Dest.Name := 'unresolved';
 end;
 
 { TBinaryOperatorHelper }

Src/AST/Myc.Ast.Printer.pas

@@ -299,7 +299,7 @@ var
 begin
     // Get the string representation of the series identifier by visiting the node.
     seriesStr := Node.Series.Accept(Self).ToString;
-    Result := TAstValue.FromText(Format('length(%s)', [seriesStr]));
+    Result := Format('length(%s)', [seriesStr]);
 end;
 
 end.

Src/AST/Myc.Ast.pas

@@ -86,7 +86,7 @@ type
         constructor Create(AParent: IScopeDescriptor);
         destructor Destroy; override;
         function Define(const Name: string): Integer;
-        function FindSymbol(const Name: string; out Index: Integer; out Depth: Integer): Boolean;
+        function FindSymbol(const Name: string; out Depth, Index: Integer): Boolean;
         function CreateScope(const AParent: IExecutionScope): IExecutionScope;
         procedure PopulateFromScope(const AScope: IExecutionScope);
         property Symbols: TDictionary<string, Integer> read FSymbols;
@@ -365,7 +365,7 @@ begin
     FSymbols.Add(Name, Result);
 end;
 
-function TScopeDescriptor.FindSymbol(const Name: string; out Index: Integer; out Depth: Integer): Boolean;
+function TScopeDescriptor.FindSymbol(const Name: string; out Depth, Index: Integer): Boolean;
 var
     currentDescriptor: IScopeDescriptor;
 begin
@@ -579,7 +579,6 @@ begin
     FBody := ABody;
     FParameters := AParameters;
     FScopeDescriptor := nil;
-    FUpvalues := []; // Initialize new field
 end;
 
 function TLambdaExpressionNode.GetUpvalues: TArray<TResolvedAddress>;
@@ -866,7 +865,7 @@ end;
 
 function TBinder.VisitIdentifier(const Node: IIdentifierNode): TAstValue;
 var
-    originalDepth, originalIndex: Integer;
+    depth, idx: Integer;
     identNode: TIdentifierNode;
     upvalueMap: TDictionary<TResolvedAddress, Integer>;
     upvalueNodes: TList<IIdentifierNode>;
@@ -877,14 +876,17 @@ begin
     if identNode.IsResolved then
         Exit;
 
-    if (FCurrentDescriptor as TScopeDescriptor).FindSymbol(identNode.Name, originalIndex, originalDepth) then
+    if (FCurrentDescriptor as TScopeDescriptor).FindSymbol(identNode.Name, depth, idx) then
     begin
-        if (originalDepth > 0) and (FUpvalueMapStack.Count > 0) then
+        if (depth > 0) and (FUpvalueMapStack.Count > 0) then
         begin
             upvalueMap := FUpvalueMapStack.Peek;
             upvalueNodes := FUpvalueNodesStack.Peek;
 
-            originalAddress.Create(akLocalOrParent, originalDepth, originalIndex, identNode.Name);
+            // Imortant: we are now in the lambda's inner scope, so decrease depth by one to point to the outer scope.
+            dec(depth);
+
+            originalAddress.Create(akLocalOrParent, depth, idx);
 
             if not upvalueMap.TryGetValue(originalAddress, upvalueIndex) then
             begin
@@ -893,12 +895,10 @@ begin
                 upvalueNodes.Add(identNode);
             end;
 
-            identNode.FResolvedAddress.Create(akUpvalue, 0, upvalueIndex, identNode.Name);
+            identNode.FResolvedAddress.Create(akUpvalue, 0, upvalueIndex);
         end
         else
-        begin
+            identNode.FResolvedAddress.Create(akLocalOrParent, depth, idx);
-            identNode.FResolvedAddress.Create(akLocalOrParent, originalDepth, originalIndex, identNode.Name);
-        end;
     end
     else
         raise Exception.CreateFmt('Undefined identifier: "%s"', [identNode.Name]);
@@ -963,7 +963,7 @@ begin
     Node.Initializer.Accept(Self);
 
     slotIndex := (FCurrentDescriptor as TScopeDescriptor).Define(Node.Identifier.Name);
-    identNode.FResolvedAddress.Create(akLocalOrParent, 0, slotIndex, Node.Identifier.Name);
+    identNode.FResolvedAddress.Create(akLocalOrParent, 0, slotIndex);
 end;
 
 { TAst }

Src/Data/Myc.Data.Scalar.pas

@@ -90,9 +90,16 @@ type
         class function FromBytes(const AValue: TScalarBytes): TScalar; static; inline;
         class function FromDecimal(const AValue: TDecimal): TScalar; static; inline;
 
+        class function StringToKind(const AName: string): TScalarKind; static;
+
         function ToString: String;
     end;
 
+    TScalarKindHelper = record helper for TScalarKind
+    public
+        function ToString: string;
+    end;
+
     // Basic data structures using the scalar type (these are not POD of course)
 
     // An array of scalar values of the same kind.
@@ -383,6 +390,38 @@ begin
     Result.Value := TScalarValue.FromUInt64(AValue);
 end;
 
+class function TScalar.StringToKind(const AName: string): TScalarKind;
+begin
+    if SameText(AName, 'integer') then
+        Result := skInteger
+    else if SameText(AName, 'int64') then
+        Result := skInt64
+    else if SameText(AName, 'uint64') then
+        Result := skUInt64
+    else if SameText(AName, 'single') then
+        Result := skSingle
+    else if SameText(AName, 'double') then
+        Result := skDouble
+    else if SameText(AName, 'datetime') then
+        Result := skDateTime
+    else if SameText(AName, 'timestamp') then
+        Result := skTimestamp
+    else if SameText(AName, 'boolean') then
+        Result := skBoolean
+    else if SameText(AName, 'char') then
+        Result := skChar
+    else if SameText(AName, 'pchar') then
+        Result := skPChar
+    else if SameText(AName, 'string') then
+        Result := skString
+    else if SameText(AName, 'bytes') then
+        Result := skBytes
+    else if SameText(AName, 'decimal') then
+        Result := skDecimal
+    else
+        raise EArgumentException.CreateFmt('Unknown scalar type name: "%s"', [AName]);
+end;
+
 function TScalar.ToString: String;
 begin
     case Kind of
@@ -645,6 +684,27 @@ begin
     Result.Create(FDef, values);
 end;
 
+function TScalarKindHelper.ToString: string;
+begin
+    case Self of
+        skInteger: Result := 'integer';
+        skInt64: Result := 'int64';
+        skUInt64: Result := 'uint64';
+        skSingle: Result := 'single';
+        skDouble: Result := 'double';
+        skDateTime: Result := 'datetime';
+        skTimestamp: Result := 'timestamp';
+        skBoolean: Result := 'boolean';
+        skChar: Result := 'char';
+        skPChar: Result := 'pchar';
+        skString: Result := 'string';
+        skBytes: Result := 'bytes';
+        skDecimal: Result := 'decimal';
+    else
+        Result := 'unknown';
+    end;
+end;
+
 initialization
     Assert(sizeof(TScalarValue) = 8);