Refactoring Binder

Src/AST/Myc.Ast.Binding.pas

@@ -75,12 +75,12 @@ type
         function GetSlotCount: Integer;
         function GetSymbols: TDictionary<string, Integer>;
     public
-        constructor Create(AParent: IScopeDescriptor);
+        constructor Create(const AParent: IScopeDescriptor);
         destructor Destroy; override;
         function Define(const Name: string): Integer;
         function FindSymbol(const Name: string; out Depth, Index: Integer): Boolean;
-        function CreateScope(const AParent: IExecutionScope): IExecutionScope;
+        function CreateScope(const Parent: IExecutionScope): IExecutionScope;
-        procedure PopulateFromScope(const AScope: IExecutionScope);
+        procedure PopulateFromScope(Scope: TExecutionScope);
         property Symbols: TDictionary<string, Integer> read FSymbols;
     end;
 
@@ -140,8 +140,9 @@ class function TAstBinder.CreateDescriptor(const Scope: IExecutionScope): IScope
 begin
     if Scope is TExecutionScope then
     begin
-        Result := TScopeDescriptor.Create(CreateDescriptor(Scope.Parent));
+        var res := TScopeDescriptor.Create(CreateDescriptor(Scope.Parent));
-        (Result as TScopeDescriptor).PopulateFromScope(Scope);
+        res.PopulateFromScope(Scope as TExecutionScope);
+        Result := res;
     end
     else
         Result := TScopeDescriptor.Create(nil);
@@ -216,7 +217,7 @@ begin
     if identNode.Address.Kind <> akUnresolved then
         Exit;
 
-    if (FCurrentDescriptor as TScopeDescriptor).FindSymbol(identNode.Name, depth, idx) then
+    if FCurrentDescriptor.FindSymbol(identNode.Name, depth, idx) then
     begin
         if (depth > 0) and (FUpvalueStack.Count > 0) then
         begin
@@ -346,7 +347,7 @@ end;
 
 { TScopeDescriptor }
 
-constructor TScopeDescriptor.Create(AParent: IScopeDescriptor);
+constructor TScopeDescriptor.Create(const AParent: IScopeDescriptor);
 begin
     inherited Create;
     FParent := AParent;
@@ -367,16 +368,16 @@ end;
 
 function TScopeDescriptor.FindSymbol(const Name: string; out Depth, Index: Integer): Boolean;
 var
-    currentDescriptor: IScopeDescriptor;
+    currentDescriptor: TScopeDescriptor;
 begin
     Depth := 0;
     currentDescriptor := Self;
-    while Assigned(currentDescriptor) do
+    while currentDescriptor <> nil do
     begin
-        if (currentDescriptor as TScopeDescriptor).FSymbols.TryGetValue(Name, Index) then
+        if currentDescriptor.FSymbols.TryGetValue(Name, Index) then
-            Exit(True);
+            exit(true);
         inc(Depth);
-        currentDescriptor := currentDescriptor.Parent;
+        currentDescriptor := currentDescriptor.FParent as TScopeDescriptor;
     end;
     Result := False;
 end;
@@ -396,14 +397,14 @@ begin
     Result := FSymbols;
 end;
 
-function TScopeDescriptor.CreateScope(const AParent: IExecutionScope): IExecutionScope;
+function TScopeDescriptor.CreateScope(const Parent: IExecutionScope): IExecutionScope;
 begin
-    Result := TExecutionScope.Create(AParent, Self, nil);
+    Result := TExecutionScope.Create(Parent, Self, nil);
 end;
 
-procedure TScopeDescriptor.PopulateFromScope(const AScope: IExecutionScope);
+procedure TScopeDescriptor.PopulateFromScope(Scope: TExecutionScope);
 begin
-    for var pair in (AScope as TExecutionScope).NameToIndex do
+    for var pair in Scope.NameToIndex do
         if not FSymbols.ContainsKey(pair.Key) then
             FSymbols.Add(pair.Key, pair.Value);
 end;

Src/AST/Myc.Ast.Nodes.pas

@@ -78,6 +78,7 @@ type
         {$endregion}
         function CreateScope(const AParent: IExecutionScope): IExecutionScope;
         function Define(const Name: string): Integer;
+        function FindSymbol(const Name: string; out Depth, Index: Integer): Boolean;
         property Parent: IScopeDescriptor read GetParent;
         property SlotCount: Integer read GetSlotCount;
         property Symbols: TDictionary<string, Integer> read GetSymbols;