[…] I cannot use like this: {$I *.RT.pas} […]
No, this won’t work, this notation only allows you to specify a
single possibly non-standard (file type hint)
suffix. It’s not replace and concatenate. You would’ve seen that if you took a look at source code lines I referenced above.
Earlier today I’ve
expanded the
wiki page on that pointing out just that.
You still can create a symbolic link
foo.RT→
foo.RT.pas, but it’s a cumbersome solution relying on file system capabilities. Also, AFAIK SCMs like the popular
git(1) won’t adequately manage them. (Or was it just
hard links that won’t be preserved? Anyway, it’s
inconvenient.)