1.3 Comparison with Emacs’s built-in Prolog mode

Emacs has a built-in mode for Prolog code, defined in the library prolog.el that comes bundled with Emacs. prolog.el aims to work with a wide variety of Prolog systems and dialects, unlike Sweep that is very tightly integrated with SWI-Prolog specifically.

If you are working with SWI-Prolog, you’ll find Sweep to be far more powerful than the built-in prolog.el. This is because Sweep leverages the Prolog parser and other analysis tools that SWI-Prolog itself uses, which give it access to highly accurate and rich information about SWI-Prolog code. If you’re using another Prolog implementation, you should stick to prolog.el as Sweep only supports SWI-Prolog.