From: Thorsten Jolitz <tjolitz@googlemail.com>
To: help-gnu-emacs@gnu.org
Subject: Re: Hash tables - how to look up values?
Date: Wed, 04 Jul 2012 16:31:02 +0200 [thread overview]
Message-ID: <87txxnbntl.fsf@googlemail.com> (raw)
In-Reply-To: 877guj62jf.fsf@gnu.org
Bastien <bzg@gnu.org> writes:
Hi Bastien,
>> I could not find such a function - does it exist already?
>
> I don't think so. But here is a start:
>
> (let (key-found)
> (maphash (lambda (key val)
> (when (equal val "my_value")
> (setq key-found key)))
> hashtest)
> key-found)
>
> Of course, the shortcoming is that it stops at the first key it finds,
> and discards multiple keys if several have the same value.
Thanks, now I even have the 'agony of choice' (is that how they call it
in English?), but I might very well need both solutions - return the
first or all values found.
--
cheers,
Thorsten
next prev parent reply other threads:[~2012-07-04 14:31 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-07-04 13:48 Hash tables - how to look up values? Thorsten Jolitz
2012-07-04 14:09 ` Teemu Likonen
2012-07-04 14:09 ` Bastien
2012-07-04 14:31 ` Thorsten Jolitz [this message]
[not found] <mailman.4023.1341409554.855.help-gnu-emacs@gnu.org>
2012-07-04 13:59 ` Pascal J. Bourguignon
2012-07-04 14:21 ` Thorsten Jolitz
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