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Re: First Class environments in CL ??
- To: NGALL@G.BBN.COM
- Subject: Re: First Class environments in CL ??
- From: David A. Moon <Moon@SCRC-STONY-BROOK.ARPA>
- Date: Mon, 12 May 86 20:20 EDT
- Cc: beckerle@MIT-XX.ARPA, common-lisp@SU-AI.ARPA
- In-reply-to: <[G.BBN.COM]12-May-86 18:57:23.NGALL>
Your ideas about what applyhook could be used for are interesting, but
not what it was historically put in for. It was put in to make it
possible for a program that steps through execution of an interpreted
program to get control after all the arguments have been evaluated and
before the function receives control. A hook for the "fvaluation" of
the function in the car of the form would be useful, perhaps, but Common
Lisp doesn't have one now. It would be better to add a third hook for
this than to incompatibly change the meaning of applyhook. Note that
the fvaluation of the function has to happen -before- the arguments
are evaluated, because that's how EVAL finds out that it's dealing with
a macro or a special form.
I would be the first to admit that this stuff could benefit from
clarification.