GNU Emacs REDUCE Integrated Development Environment

Major modes for editing and running REDUCE source code

Francis Wright

Version 1.14, April 2025

REDUCE IDE is a package that provides an Integrated Development Environment for the REDUCE computer algebra system within the GNU Emacs editor. Its two major components are Emacs Lisp libraries that provide major modes for editing REDUCE source code and running a command-line version of REDUCE in an Emacs window. It assumes that Emacs is running under a GUI such as Microsoft Windows or the X Window System under some flavour of UNIX or Linux, and displays Unicode character sets correctly. REDUCE IDE does not include REDUCE, which is available separately from SourceForge. You don't need to install REDUCE in order to edit REDUCE source code using REDUCE IDE, but if you want to run REDUCE in REDUCE IDE then you do need to install REDUCE.

REDUCE IDE now requires GNU Emacs version 29 or later and I support only Microsoft Windows and Linux.

Installation

I recommend that you install the latest complete package, which includes the manual in Info format, by following the instructions on the REDUCE IDE home page. Alternatively, you can download a package file (see Repositories and Releases below) to any convenient directory and run the Emacs command package-install-file on it. For further details, see Packages in the Emacs manual.

Documentation

The REDUCE IDE manual should be available as an Info document in Emacs, normally at the top of the Info directory, once you have installed the REDUCE IDE package. It is also available as a PDF document and a multi-page HTML document via the REDUCE IDE home page.

You can also generate the manual yourself in various formats, including info, HTML and PDF, from reduce-ide.texinfo, but you need the GNU Texinfo package. The commands I used to generate the formats that I provide are listed at the end of the file reduce-ide.texinfo. For further details, please see sections 20 to 22 of the Texinfo manual or this quick summary.

Repositories and Releases

The primary repository is GitHub. The main source files (only, see below) for release versions are also available from SourceForge. Releases as Emacs package (.tar) files are available from GitHub and in a more convenient form that is recognised by the Emacs package manager via the REDUCE IDE home page.

Main Source Files

Required:

• reduce-mode.el – REDUCE source code editing mode

Optional:

• reduce-font-lock.el – support syntactic highlighting
• reduce-delim.el – highlight matching group or block delimiters
• reduce-run.el – run REDUCE in an Emacs buffer
• reduce-extra.el – experimental optional extra functionality
• reduce-ide.texinfo – texinfo manual

To Do

• Check relation between standard and REDUCE mode key bindings.
• Check switch-to-reduce and related commands.
• Resolve REDUCE Run mode fontification clash with Comint mode.
• On Microsoft Windows, make REDUCE interruptible.
• Version 2 (maybe): use treesitter for parsing.
• Make double-click select a group or block, as for brackets.

Main Updates since REDUCE IDE 1.13

• Repair the rerun-reduce command.
• Declare the reduce-run-buffer command to autoload.
• Implement reduce-forward-word and reduce-backward-word to replace reduce-forward-identifier and reduce-backward-identifier. The aim is to move by a number or identifier, more like forward-word etc., which should improve mouse double-click selection.
• Rename reduce-identifier-mode to reduce-word-mode and the Minor Modes / Identifier Mode menu option to Minor Modes / Word Mode.
• Hide the Add "Index" Menu menu item if it has already been added, and rename it to Add Index Menu.
• Fix REDUCE mode Run REDUCE menu, and hence Run Buffer etc.: only autoload functions not already autoloaded.
• Improve some keyboard shortcuts in the REDUCE menu.
• Fix Command Mini Help menu item to show only commands intended for user access.
• Rename REDUCE Run mode menu from Run REDUCE to REDUCE, and REDUCE mode Run menu from Run REDUCE to Run-REDUCE.
• Fix key mapping for run-reduce.
• Fix reduce-run--wait-for-prompt. Sending code to REDUCE before it is running should now work better.
• Do not treat !' as a quote for syntax highlighting.
• Introduce new option reduce-etags-regexps to allow customization of tagging. Tag put(‘name, ‘psopfn, …) and put(‘name, ‘simpfn, …) as declarations of operator names, and operator declarations with up to 5 names, making it easier to track algebraic-mode operators.
• Allow REDUCE to be run from a buffer running or having run a different version of REDUCE (with a different root directory).
• Improve indentation and spacing for insert block and group commands.
• Change the default directory for reduce-tagify-dir-recursively to the parent of the current directory.