Re: count char in string [The Emacs Challenge Competition - round 2, with fallout]

[Leo Butler <leo.butler@umanitoba.ca>]

Patrick McAllister <pma@rdorte.org> writes:

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> 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

Here is a solution for interactive use that is far more flexible than
just counting characters.

I use the following a lot when editing documents with a maximum
character count:

M-< M-x replace-regexp [^[:space:]] \& RET

Or, since I bind replace-regexp to C-x a r,

M-< C-x a r [^[:space:]] \& RET

I just did that and the mini-buffer informed me there were 1232
non-space characters in the buffer. 

Leo