Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!purdue!bu-cs!oliveb!3comvax!bridge2!mdb
From: mdb@ESD.3Com.COM (Mark D. Baushke)
Newsgroups: comp.emacs
Subject: Re: Using tags and a function key
Message-ID:
Date: 23 Sep 89 07:20:54 GMT
References: <14063@shamash.cdc.com>
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Distribution: usa
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Lines: 64
>>>>> On 22 Sep 89 14:02:18 GMT, ben@nsf1.mth.msu.edu (Ben Lotto) said:
Ben> On 22 Sep 89 09:04:10 GMT,
Ben> mdb@ESD.3Com.COM (Mark D. Baushke) said:
Mark> On 21 Sep 89 15:49:56 GMT, ldk@raistlin.udev.cdc.com (ld kelley)
Mark> said:
ldk> I am trying (for the first time) to bind a function to a key.
Mark> You might try the following:
Mark> (define-key sun-raw-map "212z" '(lambda () (find-tag nil t)))
Ben> This doesn't work (at least on my emacs on my system). I get an error
Ben> which says
Ben> Wrong type argument: commandp, (lambda nil (find-tag nil t))
Oops, sorry about that. My previous lambda-expression example fails
because it is not interactive. From the documentation:
commandp:
[...]
Interactively callable functions include strings (treated as keyboard macros),
lambda-expressions that contain a top-level call to interactive ,
autoload definitions made by autoload with non-nil fourth argument,
and some of the built-in functions of Lisp.
Ben> The thing that does work here is
Ben> (defun my-find-tag-next ()
Ben> (interactive)
Ben> (find-tag nil t))
Ben> (define-key sun-raw-map "212z" 'my-find-tag-next)
Yes. This is a reasonable alternative and it allow you to get at it
via M-x my-find-tag-next as well as binding it to more than one key.
Ben> This is because the third argument to define-key must be nil, a command,
Ben> a string, a keymap, or a list consisting of elements of the form
Ben> (keymap . char).
The lambda form is equivalent to the body of a (defun name (args) BODY).
Had you defined your defun as
(defun my-find-tag-next ()
(find-tag nil t))
you would have had the same error about a wrong type argument from
commandp.
If you did not want to use the separate function my-find-tag-next, you
should be able to use the following:
(define-key sun-raw-map "212z" '(lambda () (interactive) (find-tag nil t)))
Enjoy!
--
Mark D. Baushke
mdb@ESD.3Com.COM