Subject: Re: coerce for arbitrary types
From: (Rob Warnock)
Date: Thu, 10 Apr 2008 20:27:09 -0500
Newsgroups: comp.lang.lisp
Message-ID: <>
Albert Krewinkel  <> wrote:
| The translation table for codons is currently specified using a special
| variable: I can't imagine any use case in which it is necessary to
| change the translation table often.  But allowing for a keyword argument
| is something I did consider -- and since it seems natural to you (and
| probably other people, too), I'll reconsider my design decission.

Well, remember that you can always make the default value of a
keyword argument be a special variable [or some function of a
special variable, see below]. I use that a lot with output-formatting
functions, e.g.:

    (defun format-foo (the-foo &key (stream *standard-output*) ...)
	  (format stream ...stuff...)

Or for HTML-formatting stuff the default might be
*STANDARD-OUTPUT*, whatever.


Rob Warnock			<>
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