Tail call optimization

ASTPlayground/MainForm.fmx

@@ -33,7 +33,7 @@ object Form1: TForm1
     end
     object PrettyPrintButton: TButton
       Position.X = 24.000000000000000000
-      Position.Y = 463.000000000000000000
+      Position.Y = 479.000000000000000000
       TabOrder = 3
       Text = 'Print'
       TextSettings.Trimming = None
@@ -52,7 +52,7 @@ object Form1: TForm1
     end
     object ShowScopeBox: TCheckBox
       Position.X = 24.000000000000000000
-      Position.Y = 436.000000000000000000
+      Position.Y = 452.000000000000000000
       TabOrder = 5
       Text = 'Scope'
     end
@@ -89,7 +89,7 @@ object Form1: TForm1
     end
     object ClearButton: TButton
       Position.X = 24.000000000000000000
-      Position.Y = 538.000000000000000000
+      Position.Y = 554.000000000000000000
       Size.Width = 80.000000000000000000
       Size.Height = 22.000000000000000000
       Size.PlatformDefault = False
@@ -126,13 +126,13 @@ object Form1: TForm1
     end
     object DebugBox: TCheckBox
       Position.X = 24.000000000000000000
-      Position.Y = 423.000000000000000000
+      Position.Y = 439.000000000000000000
       TabOrder = 15
       Text = 'Debug'
     end
     object FromJSONButton: TButton
       Position.X = 24.000000000000000000
-      Position.Y = 586.000000000000000000
+      Position.Y = 602.000000000000000000
       TabOrder = 16
       Text = 'From JSON'
       TextSettings.Trimming = None
@@ -140,7 +140,7 @@ object Form1: TForm1
     end
     object ToJSONButton: TButton
       Position.X = 24.000000000000000000
-      Position.Y = 616.000000000000000000
+      Position.Y = 632.000000000000000000
       TabOrder = 17
       Text = 'To JSON'
       TextSettings.Trimming = None
@@ -164,7 +164,7 @@ object Form1: TForm1
     end
     object DumpButton: TButton
       Position.X = 24.000000000000000000
-      Position.Y = 493.000000000000000000
+      Position.Y = 509.000000000000000000
       TabOrder = 20
       Text = 'Dump'
       TextSettings.Trimming = None
@@ -178,6 +178,14 @@ object Form1: TForm1
       TextSettings.Trimming = None
       OnClick = FailingUpvalueButtonClick
     end
+    object TailCallButten: TButton
+      Position.X = 24.000000000000000000
+      Position.Y = 406.000000000000000000
+      TabOrder = 23
+      Text = 'Tail calls'
+      TextSettings.Trimming = None
+      OnClick = TailCallButtenClick
+    end
   end
   object Panel2: TPanel
     Align = Client