GNU bug report logs - #79128
31.0.50; shortdoc doesn't always display the correct arglist

Previous Next

Full log

View this message in rfc822 format

From: Eli Zaretskii <eliz <at> gnu.org>
To: Robert Pluim <rpluim <at> gmail.com>, Stefan Monnier <monnier <at> iro.umontreal.ca>
Cc: 79128 <at> debbugs.gnu.org
Subject: bug#79128: 31.0.50; shortdoc doesn't always display the correct arglist
Date: Sat, 02 Aug 2025 13:44:01 +0300

> From: Robert Pluim <rpluim <at> gmail.com>
> Cc: 79128 <at> debbugs.gnu.org
> Date: Fri, 01 Aug 2025 09:56:13 +0200
> 
> >>>>> On Fri, 01 Aug 2025 10:43:24 +0300, Eli Zaretskii <eliz <at> gnu.org> said:
> 
>     Eli> Sorry, I'm confused wrt what is the bug/issue you are reporting here.
>     Eli> Are you saying that shortdoc is wrong in what it says?  If so, please
>     Eli> elaborate why, because I see nothing wrong with what it says, given
>     Eli> that shortdoc is supposed to be, well, short.
> 
> Shortdoc:
> 
>     >> (seq-empty-p arg &rest args)
> 
> C-h f
> 
>     >> (seq-empty-p SEQUENCE)
> 
> 
> The shortdoc implies that this is legal:
> 
> (seq-empty-p '() '())
> 
> but it gives:
> 
> Debugger entered--Lisp error: (wrong-number-of-arguments (1 . 1) 2)
>   #f(compiled-function (list) "Optimized implementation of `seq-empty-p' for lists." #<bytecode -0x155616500a964cb3>)(nil nil)

Ah, okay.  It would be helpful to know this from the get-go.

To answer your question:

> I imagine this is some interaction between `cl-defgeneric' with an
> implementation body, `cl-defmethod', and `help-function-arglist' (other
> functions in  the 'sequence group are also affected). C-h f gets it
> right, but I couldnʼt find a simple function in help-fns.el to get me
> the actual arglist.

The function used by "C-h f" to DTRT is help-fns--signature.  AFAICT,
in this case it basically ignores what help-function-arglist returns,
and uses the car of what help-split-fundoc returns:

      (let* ((use (cond
                   ((and usage (not (listp advertised))) (car usage)) <<<<<<

At this point, I'll step aside and leave it to Stefan and others to
explain how to solve this.

Previous Next

GNU bug tracking system
Copyright (C) 1999 Darren O. Benham, 1997,2003 nCipher Corporation Ltd, 1994-97 Ian Jackson.