Re: How to read an integer from the minibuffer

[Emanuel Berg via Users list for the GNU Emacs text editor <help-gnu-emacs@gnu.org>]

Gregory Heytings wrote:

>>> Apparently it doesn't do what I want here, namely
>>> converting "[0-9]" into "0123456789", "[0-9a-f]" into
>>> "0123456789abcdef", and so forth.
>>
>> I think it can!
>
> Please show me how...

First here is another version of "read-integer" ...

We see a problem BTW that `string-to-number' returns 0
on error!

  (string-to-number "Number Nighty Nine") ; 0

Anyway ...

(require 'cl-lib)

(defun read-integer ()
  (let ((str)
        (str-number)
        (n) )
    (cl-loop until (progn
                     (setq str (read-string "integer: "))
                     (if (string= str "0")
                         (setq n 0)
                       (setq str-number (string-to-number str))
                       (unless (= str-number 0)
                         (setq n str-number) ))
                     (integerp n)) )
    n) )

;; (read-integer)

-- 
underground experts united
https://dataswamp.org/~incal