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Re: Meaning of the hash character
From: |
Juanma Barranquero |
Subject: |
Re: Meaning of the hash character |
Date: |
Thu, 20 Nov 2008 15:16:53 +0100 |
On Thu, Nov 20, 2008 at 14:35, Nordlöw <per.nordlow@gmail.com> wrote:
> I have long wondered about the meaning of the hash character # in
> emacs lisp.
From the "Anonymous Functions" node of the Emacs Lisp Reference:
The read syntax `#'' is a short-hand for using `function'. For
example,
#'(lambda (x) (* x x))
is equivalent to
(function (lambda (x) (* x x)))
-- Special Form: function function-object
This special form returns FUNCTION-OBJECT without evaluating it.
In this, it is equivalent to `quote'. However, it serves as a
note to the Emacs Lisp compiler that FUNCTION-OBJECT is intended
to be used only as a function, and therefore can safely be
compiled. Contrast this with `quote', in *Note Quoting::.
*Note describe-symbols example::, for a realistic example using
`function' and an anonymous function.
Juanma