Fun trivia: I got a Emacs user to switch to Vim because in one of our class projects using Prolog, Emacs kept trying to highlight it as Perl (though it might be

Fun trivia: I got a Emacs user to switch to Vim because in one of our class projects using Prolog, Emacs kept trying to highlight it as Perl (though it might be valid Perl syntax now that I think about it…). When I showed him that Vim did that for an empty file, but if it detected "Prolog-y" content (IIRC, the comment marker or a `:-` did it), it defaulted to Prolog highlighting. No idea if Emacs ever fixed it (this was 2009 or so).