GNU Emacs REDUCE Integrated Development Environment

Major modes for editing and running REDUCE source code

Francis Wright

Version 1.12, March 2024

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 formally requires GNU Emacs version 27 at least although I support only GNU Emacs 29 on 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-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.

Main Updates since REDUCE IDE 1.11

• The command reduce-tagify-dir-recursively failed on the REDUCE packages directory (at least on Microsoft Windows) because the list of files is too long. Add a depth argument to reduce--directory-files-recursively to limit the recursion depth, which works around the problem. Handle errors better and improve the tagging menu tooltips.
• Fix a bug in the display of the current procedure name.
• Incompatible changes:
  • Change the option reduce-run-commands so that a REDUCE command is a list of strings rather than a single string, which allows spaces in both the command and its arguments. Automatically update a saved value to the new structure and offer to edit and/or save it. Add a facility to set the environment variable reduce. Better labelling of the customization buffer.
  • Rename the option reduce-run-installation-directory to reduce-root-dir-file-name and make it a directory file name rather than a directory name, i.e. remove the final directory separator. This makes it suitable as the default value of the environment variable reduce.
  • Remove the option reduce-run-MSWin-drives and incorporate its use into the definition of reduce-root-dir-file-name, without using any external programs.
• Introduce the shorthand $reduce to be replaced at the start of strings (other than Name) in reduce-run-commands and reduce-packages-directory with the value of reduce-root-dir-file-name before they are used.
• On Microsoft Windows, run REDUCE directly by default rather than via the .bat files, which avoids the query "Terminate batch job (Y/N)?" when REDUCE is killed (such as by attempting to interrupt it). Keep the .bat commands for now for comparison, but update the default CSL REDUCE command to preserve the current working directory. Remove special support for PSL REDUCE, which is no longer needed from REDUCE revision 6726. Note that if you have customized reduce-run-commands then you may need to erase the customization (at least for PSL REDUCE) and then re-customize it.
• Update manual.