Online Developer Meeting (2021-05-25)

• Date: Tuesday, May 25, 2021 @ 18:00 UTC
• Location: https://meet.jit.si/octave-dev-2021-05-25

Todays topics

• Meet and greet 5 minutes before meeting (audio testing).

Discourse

• General question about the acceptance.
  • We like it.
• Continue to no longer actively advertise the mailing-lists.

Octave 6.3.0

• 6.3 Release Checklist
• Bug #60620: octave-cli crashes when interacting with Java libraries
  • Not blocking release.
  • jwe takes a look.
• ABI breaking minor release? https://octave.discourse.group/t/more-frequent-minor-releases/1127
  • Not blocking release.
  • Do not increase major version number, only API version.

Octave releases

• Keep the current versioning scheme https://hg.savannah.gnu.org/hgweb/octave/file/1077d7c87fcc/etc/HACKING.md#l301.
• Only one major release per year.
  • Should include new features.
  • Developer time is limited, more not doable.
  • More frequent minor releases, not 100% perfect, promise to try to keep API/ABI compatibility.
• Better error than crash on API/ABI changes.
  • It seems this problem occurred with development versions of Octave.
    • No mercy for developers: they hopefully know what they are doing, have to cope with breaking changes.
    • Normally the API version of oct files is checked, thus it should not have crashed and rather have warned.
    • Contrary with development version, even after breaking changes, the API is only incremented once for the release. This might have caused the trouble.
• Octave on MS Windows, Linux, macOS usually has somehow a compiler available (unlike Matlab on MS Windows), thus recompiling the oct files is annoying, but possible.

GitHub Actions

• Markus gave a small presentation of this project.
  • https://github.com/gnu-octave/octave/actions (need to be member of the https://github.com/gnu-octave organization, just ask on Discourse https://octave.discourse.group/t/github-gitlab-organization-for-gnu-octave/178).
  • Not 100% perfect yet, but already in a good shape.
  • CodeQL static code analysis
  • Help with macOS wanted

QScintilla signal/slot problem

• Bug #60469
• On MS Windows only for QScintilla the "safer" signal/slot changes seem to not work.
  • Revert it until the problem is identified.

Previous topics

The following items were not discussed. Just some links to progress on those items are displayed.

MXE Octave branches

• Which changes should go on which branch?
  • "default": everything new
  • "release": conservative updates

Buildbots

• Find out how to trigger a build on changes in two repositories?
  • Realization: https://github.com/gnu-octave/octave-buildbot/blob/cac9a03f201200f494d6c17d452564c486f8128e/master/defaults/master.cfg#L96-L132

GitHub

• Markus added a folder ".github" to the Octave main repo?
  • How are the experiences so far? 😉

String class strategy

• Strategy for transition to string class syntax (incompatible to current double-quoted character vectors in Octave)?
  • Issue treatment of escape characters (first interpreted when Xprintf is applied).
    • https://www.mathworks.com/help/matlab/ref/string.html
• Suggestion to implement an initial string class at one point
  • Many existing Octave code (packages) might break.
  • In the transition time using
    • Octave .oct-config files to manage how double quoted strings are treated
    • Implement convertStringsToChars and solve issue per function basis (Matlab compatible, probably straight forward, but many changes).
      • https://www.mathworks.com/help/matlab/ref/convertstringstochars.html
• Initial implementation by Andrew Janke
  • https://github.com/apjanke/octave-tablicious/blob/master/inst/string.m
  • http://blog.apjanke.net/2019/04/20/matlab-string-representation-is-a-mess.html

Classdef

• Wish to define classdef classes from C++ "nicely" (currently only from m-files comfortable usable).
• This would also help implementing the string class.

C++17

General consensus was to stay with C++11 until a "killer application" shows up that justifies changing to a newer standard.

See also

• Next meeting: Online Developer Meeting (2021-06-22)
• Last meeting: Online Developer Meeting (2021-04-27)