Re: Proposal: Forwards-Compatibility Library for Emacs

[Lars Ingebrigtsen <larsi@gnus.org>]

Philip Kaludercic <philipk@posteo.net> writes:

> So before I continue working on this, I would like to ask if there is
> any interest/there are any objections to providing such a library?

In the past, it was frowned upon to create these shims because of
"pollution" and "cleanliness" and all that sort of stuff -- when
something breaks, the question becomes "which version of `when-let*' was
that, then?" which most users aren't able to answer.

On a practical level, I think it's likely that people are using the
presence of certain features as a proxy for Emacs versions, and defining
a function like this might break some people's code.  (I.e., they're
testing for the presence of `when-let*' to see whether they should do
something totally unrelated that was introduced in a specific Emacs
version, like :extend the face.)

That said, it's just so much more practical for package authors to have
these compat shim libraries.  I naughtily had a gnus-compat.el library
in the external Gnus distribution for a decade that did pretty much what
you're doing here, and I can't recall anything breaking.

So I'm for it.

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no