Re: cperl-mode: Eliminating references to obsolete packages

["Harald Jörg" <haj@posteo.de>]

Stefan Monnier writes

>> I'd like to prepare a patch which removes all conditionals querying
>> these functions, the associate code branches, and related
>> customization variables.
> 
> Sounds good!
> In the (distant) past I tended to try and keep the code unchanged to
> minimize conflict with Ilya's upstream version, but AFAIK nowadays there
> is no "upstream version" any more, so we can clean it up.  We may want
> to keep the compatible with some older Emacsen (like Emacs-25), e.g. if
> we want to distribute the code via GNU ELPA.

I guess Ilya has retired?  Should I try to contact him?

I want to keep it compatible with at least Emacs 26, since this is the
version currently available with "stable" Linux distributions, and
this is the version used by Perlers who have shown interest or given
feedback so far.  As of now, I have found two commits which violate
that, one of which I consider fairly irrelevant (timing font-locking:
This was an issue 20 years ago, when computers where a bit slower).

I am unsure about the procedure: Should the backwards-compatible
version live in a separate branch on Emacs?  In the ELPA repository?
Or should incompatible changes just be avoided in the master branch?
There's still a lot to be done to modernize cperl-mode.el, and
manually keeping two versions in synch seems ugly.

Right now, I was lazy enough to create a branch in my own GitHub
repository which follows the master branch in the Emacs repository,
but eliminated one change so far which broke Emacs 26 compatibility:
The function format-prompt is new in Emacs 28.
-- 
Cheers,
haj