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From: Stefan Monnier <monnier@iro.umontreal.ca>
To: emacs-devel@gnu.org
Subject: Re: [PATCH] Add new function to test whether a key is present in a hash table.
Date: Thu, 15 Feb 2018 20:59:12 -0500	[thread overview]
Message-ID: <jwvinaxbsvq.fsf-monnier+gmane.emacs.devel@gnu.org> (raw)
In-Reply-To: eebe25b9-e379-4269-9a9f-78de96e385d7@default

> But isn't it better to define this in C?

To me the answer is usually no, unless it's speed-critical.


        Stefan


PS: I think a more interesting function to provide would be some
gethash-ref which would return some kind of "reference" to the entry, so
we can afterwards update that hash-table entry without (re)computing the
hash (i.e. some kind of equivalent to `intern` after which you can just
do `set` which doesn't involve hashing any more).  But that would imply
a fairly significant amount of design to make it work.




  reply	other threads:[~2018-02-16  1:59 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-02-15 20:34 [PATCH] Add new function to test whether a key is present in a hash table Philipp Stephani
2018-02-15 22:03 ` Clément Pit-Claudel
2019-04-19 17:33   ` Philipp Stephani
2018-02-15 22:59 ` Stefan Monnier
2018-02-16  1:03   ` Drew Adams
2018-02-16  1:59     ` Stefan Monnier [this message]
2018-02-16  2:50       ` Drew Adams
     [not found] <<20180215203406.64372-1-phst@google.com>
2018-02-15 22:08 ` Drew Adams
2018-02-15 23:35   ` Eric Abrahamsen
2018-02-16  6:51   ` John Wiegley
2018-02-18 14:29     ` Richard Copley
2018-02-19  6:02       ` John Wiegley
2018-02-19 17:26     ` Drew Adams

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