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 17:59:22 -0500 [thread overview]
Message-ID: <jwv8tbtg8tk.fsf-monnier+gmane.emacs.devel@gnu.org> (raw)
In-Reply-To: 20180215203406.64372-1-phst@google.com
> Such a function is useful because in Emacs Lisp, 'gethash' cannot
> return whether the key is present as in Common Lisp, and using
> 'gethash' alone to test for presence is nontrivial.
We could also implement it in Elisp:
(defun hash-table-contains-p (key table)
(let ((x '(:hash-table-contains-p)))
(not (eq x (gethash key table x)))))
-- Stefan
next prev parent reply other threads:[~2018-02-15 22:59 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 [this message]
2018-02-16 1:03 ` Drew Adams
2018-02-16 1:59 ` Stefan Monnier
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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