bug#45619: 28.0.50; pcase-let on MacOS doesn't work

[Stefan Monnier]

Lars Ingebrigtsen [2022-02-12 08:46:02] wrote:
> Michael Heerdegen <michael_heerdegen@web.de> writes:
>>> (pcase-let ((`(,default-directory) '( "/tmp/")))
>>>     (call-interactively 'find-file))
>>>
>>> Expected behavior: Find file in "/tmp/"
>>> Observed behavior: Find file in "~"
>>
>> AFAICT the issue here is that `pcase-let' always creates lexically
>> scoped bindings, even for special variables.  That can be surprising.
>>
>> @Stefan, what can we do?  Document better?  Add compiler warnings?  Or
>> is it possible to "fix" this?
> I tried the form in Emacs 29, and I got the expected behaviour here.  So
> was this fixed since this bug was reported?  (But I only tested on Debian.)

Hmm... I doubt it's fixed in all cases.
I still think pcase should emit a warning when asked to bind
a dynamically scoped variable.


        Stefan