GNU bug report logs - #44166
pcase-exhaustive doc string could be more didactic

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Message #5 received at submit <at> debbugs.gnu.org (full text, mbox):

From: Stefan Kangas <stefan <at> marxist.se>
To: bug-gnu-emacs <at> gnu.org
Subject: pcase-exhaustive doc string could be more didactic
Date: Thu, 22 Oct 2020 20:30:41 -0700

The doc string of `pcase-exhaustive' could be more didactic.  It says:

    pcase-exhaustive is a Lisp macro in ‘pcase.el’.

    (pcase-exhaustive EXP &rest CASES)

    The exhaustive version of ‘pcase’ (which see).
    If EXP fails to match any of the patterns in CASES, an error is signaled.

From reading the code, I understand that this is the same as pcase, but
signals an error if there is no match?  If this is correct, may I
suggest to amend the doc string as follows?

    The exhaustive version of ‘pcase’ (which see).
    If EXP fails to match any of the patterns in CASES, an error is
    signaled.
    In contrast, `pcase' will only return nil if there is no match.

Also, should it be added to the ELisp manual?

Message #8 received at 44166 <at> debbugs.gnu.org (full text, mbox):

From: Stefan Kangas <stefan <at> marxist.se>
To: 44166 <at> debbugs.gnu.org
Cc: monnier <at> iro.umontreal.ca
Subject: Re: bug#44166: pcase-exhaustive doc string could be more didactic
Date: Sun, 19 Sep 2021 08:34:16 -0700

tags 44166 + fixed
close 44166 28.1
thanks

Stefan Kangas <stefan <at> marxist.se> writes:

> The doc string of `pcase-exhaustive' could be more didactic.  It says:
>
>     pcase-exhaustive is a Lisp macro in ‘pcase.el’.
>
>     (pcase-exhaustive EXP &rest CASES)
>
>     The exhaustive version of ‘pcase’ (which see).
>     If EXP fails to match any of the patterns in CASES, an error is signaled.
>
>>From reading the code, I understand that this is the same as pcase, but
> signals an error if there is no match?  If this is correct, may I
> suggest to amend the doc string as follows?
>
>     The exhaustive version of ‘pcase’ (which see).
>     If EXP fails to match any of the patterns in CASES, an error is
>     signaled.
>     In contrast, `pcase' will only return nil if there is no match.

There have been no comments here within a year, so I've now pushed a
change like this to master (commit 86837a87b7).

> Also, should it be added to the ELisp manual?

I guess not.  Closing this bug.

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