BTW, if there are major objections to the language, I should point out
that the new `buffer-match-p' in Emacs 29 uses the same language and has
already found usage in a number of spots in core Emacs. There would
still be time to address any issues you might have, and avoid a
long-term mistake.
For me, it looks like match-buffers is reinventing
cl-remove-if-not and match-buffer-p is reinventing ... unary predicate
function of a buffer?
I'm not fond of these mini-languages because they're less expressive, they
end up being only minimally less complicated and bug-prone, they can't
automatically be byte-compiled for efficiency, and they can't automatically
be byte-compiled for correctness/diagnostics. If one makes a mistake,
the backtrace is much more complicated.
So these mini-languages may make sense to define filters in thunderbird or
something, but throwing Elisp away here generally doesn't make sense to me.
But there may be exceptions (although this project.el one doesn't seem one
of them) so why don't you show examples of use of these new helpers and
so we can compare side by side with the Elisp-only alternative.
João