Re: Quick pcase question

[phillip.lord@russet.org.uk (Phillip Lord)]

Eric Abrahamsen <eric@ericabrahamsen.net> writes:

> I'm enjoying pcase quite a bit, particular when employed as a kind of
> improved destructuring-bind. I think I've got the hang of most of it
> (despite the docs being a bit... succinct)

They are being improved! It might be worth looking at the docs in
the Emacs-25 pre-releases.


> What I want to do is: "if this atom matches a predicate, the whole
> pattern matches, and also bind the atom to this local variable."
>
> Right now I'm making that work like this:
>
> (setq tst '(symbolla . "I'm the string"))
>
> (pcase tst
>   (`(symbolla . ,(and x (pred stringp)))
>    (message "cdr is a string: %s" x)))
>
> Is the ",(and x (pred stringp))" part really the simplest way of doing
> that? It just seems a little unintuitive.


I think that's it I am afraid. Don't trust me though, I am no expert.

Phil