Merge branch 'master'
Support new DCG SSU rules
; * sweep.texi (Top-level Interaction): Mention 'h' for help.
Sweep is an embedding of SWI-Prolog in Emacs. It provides an interface for executing Prolog queries and consuming their results from Emacs Lisp. Sweep further builds on top of this interface and on top of the standard Emacs facilities to provide advanced features for developing SWI-Prolog programs in Emacs.
Some of the main benefits that Sweep brings to working with Prolog code in Emacs are:
These features and others, along with many options that Sweep provides for you to customize its behavior, are documented in the Sweep manual.
Installing Sweep requires:
Sweep is available from NonGNU ELPA, to install it simply type in
Emacs M-x package-install RET sweeprolog RET
.
Note that in Emacs prior to version 28, you need to explicitly enable NonGNU ELPA by adding something like the following to your Emacs configuration:
(with-eval-after-load 'package
(add-to-list 'package-archives '("nongnu" . "https://elpa.nongnu.org/nongnu/")))
To upgrade Sweep to a newer version, do M-x package-upgrade sweeprolog RET
.
After installing the sweeprolog
Elisp library, load it into Emacs:
(require 'sweeprolog)
Sweep tries to find SWI-Prolog by looking for the swipl
executable
in the directories listed in the Emacs variable exec-path
. When
Emacs is started from a shell, exec-path
is initialized from the
PATH
environment variable which normally includes the location of
swipl
in common SWI-Prolog installations. If the swipl
executable
cannot be found via exec-path
, you can tell Sweep where to find it
by setting the variable sweeprolog-swipl-path
to point to it:
(setq sweeprolog-swipl-path "/path/to/swipl")
All set! You can now use Sweep for Prolog development and for integrating Prolog into your Emacs Lisp code. For a full description of the different features of Sweep, see the Sweep manual.