{$IF FILEEXIST(file)} {$ENDIF}
The ability to check the presence of a file before doing include will give very flexible features
{$IF FILEEXIST(file)}
MyStr:={$INCLUDESTRINGFILE file};//if allow https://gitlab.com/freepascal.org/fpc/source/-/issues/25536
{$ELSEIF}
MyStr:='DefaultValue';
{$ENDIF}
оr
{$IF FILEEXIST(version.inc)}
{$INCLUDE version.inc}
{$ELSEIF}
Version:='unversionized';
{$ENDIF}
separate from #25536
Edited by Andrey Zubarev