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From: Patrick McAllister <pma@rdorte.org>
To: help-gnu-emacs@gnu.org
Subject: Re: count char in string [The Emacs Challenge Competition - round 2, with fallout]
Date: Thu, 29 Oct 2020 14:53:12 +0100	[thread overview]
Message-ID: <875z6tqh10.fsf@pmatoe> (raw)
In-Reply-To: <87r1pj41wa.fsf@zoho.eu>

On Wed, Oct 28 2020, Emanuel Berg via Users list for the GNU Emacs text editor wrote:

> round 2:
>
> Very simple: we are looking for a function that returns the number of
> occurrences of a char in a string.
>
> Emanuel Berg's solution:
>
> (require 'cl-lib)
> (defun count-char-in-string (the-char str)
>   (let ((c  (if (characterp the-char) the-char (string-to-char the-char)))
>         (cs (string-to-list str)) )
>     (cl-count c cs) ))
> ;; (count-char-in-string ?a "Emacs skills kills") ; 1

I had this lying around:

(defun count-char-in-string (char string)
  "Count CHARS in STRING (after normalizing it)."
  (length
   (cl-remove-if-not
    (lambda (x) (= char x))
    (append (ucs-normalize-NFKC-string string) nil))))

-- 
Patrick



  parent reply	other threads:[~2020-10-29 13:53 UTC|newest]

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-10-28  0:42 count char in string [The Emacs Challenge Competition - round 2, with fallout] Emanuel Berg via Users list for the GNU Emacs text editor
2020-10-28  8:04 ` Corwin Brust
2020-10-28 17:19   ` Noam Postavsky
2020-10-29  1:15     ` Corwin Brust
2020-11-29  3:44       ` Emanuel Berg via Users list for the GNU Emacs text editor
2020-11-28  1:26   ` Emanuel Berg via Users list for the GNU Emacs text editor
2020-11-28 17:40     ` Benjamín Buccianti
2020-10-29  1:46 ` Benjamín Buccianti
2020-10-29 10:38 ` Stephen Berman
2020-10-29 16:13   ` Drew Adams
2020-10-29 13:53 ` Patrick McAllister [this message]
2020-10-29 17:52   ` Leo Butler
2020-10-29 22:44     ` Jean Louis
2020-10-30 11:09       ` Leo Butler
2020-10-30 11:36         ` Joost Kremers
2020-10-30 11:53         ` Jean Louis

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