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From: "Björn Bidar" <bjorn.bidar@thaodan.de>
To: Drew Adams <drew.adams@oracle.com>
Cc: Heime <heimeborgia@protonmail.com>,
	 Heime via Users list for the GNU Emacs text editor
	<help-gnu-emacs@gnu.org>
Subject: Re: [External] : Exiting from mapc
Date: Wed, 01 Jan 2025 21:40:04 +0200	[thread overview]
Message-ID: <38521.53879577$1735760439@news.gmane.org> (raw)
In-Reply-To: <DS7PR10MB52327BA9069DB9B925A9FB62F30B2@DS7PR10MB5232.namprd10.prod.outlook.com> (Drew Adams's message of "Wed, 1 Jan 2025 02:02:44 +0000")

Drew Adams <drew.adams@oracle.com> writes:

>> >> How can I exit when encountering 'safg or 'nogo
>> >
>> > As usual, wrap with a `catch', and `throw' to it whenever you like.
>> 
>> Should dolist be better in this context anyway?
>
> Of course, but it doesn't answer his question. ;-)

Sure I'm just saying this as an added comment. macp can be expensive
unless you invoke a handler for function anyway or use a mapc style
filter function such as seq-filter.

> If a plain iteration, with no intermediate escape
> to throw a value, is appropriate for what you want
> to do, then by all means use it.
>
> IOW, don't go catching and throwing willy nilly.
> Like `GO TO'.
>
> `dolist' and `mapc' etc. don't let you escape;
> you must go through the whole list.  Catch and
> throw are available for when you need to get out
> and return or do something directly, and not
> waste time running down the rest of the list for
> nothing.

Another approach is to use second status variable when using while.
Are there instances where a throw and catch does not work in while loop?



  reply	other threads:[~2025-01-01 19:40 UTC|newest]

Thread overview: 17+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-12-31 19:35 Exiting from mapc Heime via Users list for the GNU Emacs text editor
2024-12-31 20:13 ` [External] : " Drew Adams
2024-12-31 20:20   ` Heime via Users list for the GNU Emacs text editor
2024-12-31 22:30     ` Drew Adams
2025-01-01 23:14       ` Heime via Users list for the GNU Emacs text editor
2025-01-02  0:31         ` Joel Reicher
2025-01-02 10:33           ` Jean Louis
2025-01-03  0:23             ` Joel Reicher
2025-01-02  0:33         ` Drew Adams
2025-01-02  2:21         ` Eduardo Ochs
2025-01-01  1:53   ` Björn Bidar
     [not found]   ` <87wmffwb8w.fsf@>
2025-01-01  2:02     ` Drew Adams
2025-01-01 19:40       ` Björn Bidar [this message]
     [not found]       ` <874j2iwcff.fsf@>
2025-01-01 20:00         ` Drew Adams
2025-01-01 21:09           ` Björn Bidar
     [not found]           ` <87a5cautqb.fsf@>
2025-01-01 21:59             ` Drew Adams
2025-01-02 10:53 ` Jean Louis

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