Re: Replace trivial pcase occurrences in the Emacs sources

[Andy Moreton]

On Thu 25 Oct 2018, Stefan Monnier wrote:

>> This raises the question: can we develop a clearer alternative spec
>> for a new constuct?  Would people like to try out various alternatives?
>
> Indeed, this can be done without having to re-implement the underlying
> machinery since you can easily use a macro-layer on top of pcase
> (either via normal defmacro or via pcase-defmacro, or both).

...which does not help existing users, who are still dealing with
inadequate documentation of the pcase family of macros, and with the
baffling syntax. pcase-lambda, pcase-let, pcase-let*, and pcase-dolist
still have no meaningful documentation, and are not even mentioned in
the manual.

Pattern matching is a useful facility, but pcase is woefully hard to use
correctly, as the existing (mis-)usage shows. Something that is
significantly easier to read and comprehend is needed.

    AndyM