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From: Drew Adams <drew.adams@oracle.com>
To: Raffaele Ricciardi <rfflrccrd@gmail.com>, help-gnu-emacs@gnu.org
Subject: RE: How does `undo` know that `keyboard-quit`has been called?
Date: Fri, 7 Nov 2014 14:02:48 -0800 (PST)	[thread overview]
Message-ID: <b6e3f243-807f-4528-b604-99e91b282d7b@default> (raw)
In-Reply-To: <cc4sbmF8oioU1@mid.individual.net>

> I would like to write a command that behaves like `undo`, that is: a
> command that reverses its behaviour when the user calls `keyboard-
> quit`.
>   I have read the Lisp code for both `undo` and `keyboard-quit` and
> I can't understand how `undo` achieves such behaviour. (I know that I
> could always advise `keyboard-quit`.)

If you just want to stop doing something when a user hits `C-g'
then wrap `condition-case' around the doing of the something:

(condition-case nil
     (do-something)
  (quit (handle-C-g-however-you-like)))

See the Elisp manual, node `Handling Errors`.



      parent reply	other threads:[~2014-11-07 22:02 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-11-07 21:36 How does `undo` know that `keyboard-quit`has been called? Raffaele Ricciardi
2014-11-07 22:02 ` Stefan Monnier
2014-11-07 22:02 ` Drew Adams [this message]

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