RTL/VCL cover file

User interface > Translation options > Input options > RTL/VCL cover file

The Visual Component Library (VCL) is a Delphi library for an easy development of Windows user interfaces (GUI). Thsi library exists in Delphi only. A translation to C++ might be possible, but would be a very big task even with Delphi2C++, because the code of the VCL is a link to the Windows API and Delphi2Cpp would have to know the exact specifications of this API to make a correct translations. Much parts of the  Many parts of the RTL are also hardly translatable.

The use of an RTL/VCL cover file allows to simulate code parts that are difficult to translate and then to substitute them in C++.  A very simple would be the following:

unit VclCover;

interface

//uses ...;

type

TCustomControl = class

public

Width: Integer;

Height: Integer;

Left: Integer;

Top: Integer;

end;

end.

If then the following code would have to be translated:

var

  Control : TCustomControl;

begin

  Control.With := ...  

Delphi2Cpp would know by use of the cover file that on the right side of the assignment an integer is expected. All symbols, that Delphi2Cpp tries to look up in files that are used for the translation, but are not to be translated themselves, are tried to be looked up in the cover file first. If the symbol is found there a further lookup isn't made.

This page belongs to the Delphi2Cpp Documentation