unlink question

Hi All,

Fedora 41
rakudo-pkg-2024.7.0-01.x86_64

I had a problem where this would randomly not
delete the file and not give me the error print
when delete failed:

    if not unlink $OldFileName {
       PrintRedErr( "Unable to Delete OldFileName <$OldFileName>\n" );
    }


But this change fix it right up:

    unlink $OldFileName;
    if $OldFileName.IO.e  {
       PrintRedErr( "Unable to Delete OldFileName <$OldFileName>\n" );
    }


What in the world did I do wrong on the original?

Yours in confusion,
-T