[fpc-pascal] Class Helper to implement an Interface

[Marcos Douglas B. Santos]

Hi,
Can I make a class helper to implements an Interface in an existing class?

For example, TStringList class has Find:

public function TStringList.Find(const S: string; out Index: Integer):Boolean;

Imagine an IFinder interface with the same method (only this method).
So, is it possible to make TStringList to implement IFinder using a
helper? If yes, which is the syntax?

Thanks,
Marcos Douglas