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From: Stefan Monnier via Users list for the GNU Emacs text editor <help-gnu-emacs@gnu.org>
To: help-gnu-emacs@gnu.org
Subject: Re: Advice functions: required args that byte-compiler warns are unused
Date: Wed, 03 Nov 2021 15:04:34 -0400	[thread overview]
Message-ID: <jwvr1bxcbbb.fsf-monnier+emacs@gnu.org> (raw)
In-Reply-To: SJ0PR10MB5488BC2AAC9C79E533B0B366F38C9@SJ0PR10MB5488.namprd10.prod.outlook.com

>  (defun my-foo-after-advice (&rest args)
>    "..."
>    (ignore args)      ; Quiet the byte-compiler.
>    (do-stuff-that-doesnt-refer-to-ARGS))

Use 

    (defun my-foo-after-advice (&rest _args)

or just

    (defun my-foo-after-advice (&rest _)

> Suppose function `foo' requires 3 arguments:
>
>  (defun foo (a b c) ...)

Here you can use

    (defun foo (_a _b _c) ...)

tho you can also use

    (defun foo (&rest _) ...)

since you advice doesn't have to only accept exactly the same args as
the function it advises: it is free to accept *more* use-cases (and it's
often a good idea to do so, in case the advised function grows some
&optional arguments in the future).


        Stefan




      reply	other threads:[~2021-11-03 19:04 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-11-03 17:53 Advice functions: required args that byte-compiler warns are unused Drew Adams
2021-11-03 19:04 ` Stefan Monnier via Users list for the GNU Emacs text editor [this message]

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