bug#30425: 27.0.50; Return value of `pcase' not specified if no patterns match

bug#30425: 27.0.50; Return value of `pcase' not specified if no patterns match

[Philipp]

Neither the manual nor the docstring of `pcase' specify what happens if
no patterns match.  Probably the intention and actual behavior is that
it returns nil in that case, but that should be documented in the manual
and the docstring.


In GNU Emacs 27.0.50 (build 49, x86_64-apple-darwin17.4.0, NS appkit-1561.20 Version 10.13.3 (Build 17D47))
 of 2018-02-11 built on p
Repository revision: 13f4b518d0bb7cb4536d341a2a2c8d0b76f75f6b
Windowing system distributor 'Apple', version 10.3.1561
System Description:  Mac OS X 10.13.3

Recent messages:
For information about GNU Emacs and the GNU system, type C-h C-a.

Configured using:
 'configure --with-modules --without-pop --with-mailutils
 --enable-gcc-warnings=yes --enable-checking
 --enable-check-lisp-object-type 'CFLAGS=-ggdb3 -O0''

Configured features:
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JSON

Important settings:
  value of $LANG: de_DE.UTF-8
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Major mode: Lisp Interaction

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Memory information:
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bug#30425: 27.0.50; Return value of `pcase' not specified if no patterns match

[Noam Postavsky]

tags 30425 fixed
close 30425 26.1
quit

Philipp <p.stephani2@gmail.com> writes:

> Neither the manual nor the docstring of `pcase' specify what happens if
> no patterns match.  Probably the intention and actual behavior is that
> it returns nil in that case, but that should be documented in the manual
> and the docstring.

Done in emacs-26.

[1: e50196e8a9]: 2018-03-31 00:50:37 -0400
  Document return value of pcase (Bug#30425)
  https://git.savannah.gnu.org/cgit/emacs.git/commit/?id=e50196e8a96216f1fd69f9257cddd8d76ad2ac78