Prolog uses .pl and because of the Perl conflict occasionally .pro: http://www.swi-prolog.org/pldoc/man?section=fileext http://www.swi-prolog.org/pldoc/man?sect

Prolog uses .pl and because of the Perl conflict occasionally .pro: http://www.swi-prolog.org/pldoc/man?section=fileext http://www.swi-prolog.org/pldoc/man?section=fileext I still found a autocmd Filetype pl set syntax=prolog in my vim config from my Prolog days.