lib: remove lib/demo.g

[ssiccha]

Description

The functions in this file are unused, undocumented and a proper
demo functionality is available via the browse package.

Text for release notes

Removes the file lib/demo.g. The functions in this file are unused, undocumented and a proper
demo functionality is available via the browse package.

Checklist for pull request reviewers

• proper formatting

• usage of relevant labels

  1. either release notes: not needed or release notes: to be added
  2. at least one of the labels bug or enhancement or new feature
  3. for changes meant to be backported to stable-4.X add the backport-to-4.X label
  4. consider adding any of the labels build system, documentation, kernel, library, tests

• runnable tests

• lines changed in commits are sufficiently covered by the tests

• adequate pull request title

• well formulated text for release notes

• relevant documentation updates

• sensible comments in the code

[stevelinton]

I have some concerns with this. The old demo functions certainly used to be quite heavily used (of course such use would be in peoples private methods for doing demonstrations in talks, not in any package) and the alternative from Browse requires ncurses and readline neither of which is reliably available, or problem-free, on all systems.

It is true that I've seen far fewer talks with demonstrations in recent years, and many of those used Jupyter or something else to manage them, but I think this, at least, needs wider discussion. If we want to keep this version, I can happily document it.

[olexandr-konovalov]

In particular this file is read by SCSCP package: https://github.com/gap-packages/scscp/blob/master/demo/rundemo.g

[ssiccha]

Ok, if people and packages still use it then it might be nice to document some functions. I'll open an issue for that and tag you on it @stevelinton. Thanks. :)