anchor.diff:  
       procedure Clear;
       function Peek: TSyntaxNode;
  -    procedure Pop;
  +    function Pop: TSyntaxNode;
   
       function Push(Typ: TSyntaxNodeType; SetPositionAttributes: Boolean = True): TSyntaxNode; overload;
       function Push(Node: TSyntaxNode; SetPositionAttributes: Boolean = True): TSyntaxNode; overload;
  
positive.code: 
  procedure TPasSyntaxTreeBuilder.InterfaceType;
  begin
    FStack.Peek.SetAttribute(sTYPE, 'interface');
    inherited;
  end;
  
  procedure TPasSyntaxTreeBuilder.LabelId;
  
negative.code:   Result := FStack.Peek;
  end;
  
  function TNodeStack.Pop: TSyntaxNode;
  begin
    Result := FStack.Pop;
  end;
  
  function TNodeStack.Push(Node: TSyntaxNode; SetPositionAttributes: Boolean): TSyntaxNode;
  