Re: "break" and "continue" in Emacs Lisp

[Pascal Bourguignon <spam@mouse-potato.com>]

"Herbert Euler" <herberteuler@hotmail.com> writes:

> Hello,
>
> I don't know how to write an Emacs Lisp program that's equal
> to the following C program, because of break and continue:
>
>     i = 0;
>     while (i++ < 100)
>         if (i == 25)
>             continue;
>         else if (i == 75)
>             break;
>
> For break, I now write it in this way:
>
>     (let ((i 0))
>       (while (and (< i 100) (not (eq i 75)))
>         () ; operations here
>         (setq i (1+ i))))
>
> Perhaps catch and throw also work.

(require 'cl)
(loop with i = 0
      while (< (incf i) 100)
      do (unless (= i 25)
           (when (= i 75) (return))
           (princ i) (princ " ")))

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74


> For continue, this can work:
>
>     (let ((i 0))
>       (while (< i 100)
>         (if (not (eq i 25))
>             () ; operations here
>           ())
>         (setq i (1+ i))))
>
> I don't think this is clear and straightforward. Is there any better
> solution? Is there no goto in Emacs Lisp?

No, not in emacs lisp.

-- 
__Pascal Bourguignon__                     http://www.informatimago.com/

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