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- To: Rice@sumex-aim.stanford.edu
- Subject: LetRec
- From: barmar@Think.COM
- Date: Sun, 10 Apr 88 01:10:45 EDT
- Cc: Common-Lisp@sail.stanford.edu
- In-reply-to: James Rice's message of Fri, 8 Apr 88 16:16:43 PDT <12388917560.13.RICE@SUMEX-AIM.Stanford.EDU>
Date: Fri, 8 Apr 88 16:16:43 PDT
From: James Rice <Rice@sumex-aim.stanford.edu>
Mmmm, I see what you're getting at. Maybe it's a wimp-out
but how about:
It is an error to use the named structure in the definition
of a letrec variable as an argument to a strict operator
during the evaluation of its definition.
What is the definition of "strict operator"? Is a user-defined
function a strict operator?
e.g. (letrec ((foo (+ 1 foo))) <---- error
(letrec ((bar (cons 42 bar))) <--- ok.
In this case, I don't think this facility is appropriate for the
standard language. Are there any Lisp implementations that have such
a facility? If not, I think it would be a bad idea to suddenly thrust
it into the standard.
- From: James Rice <Rice@SUMEX-AIM.Stanford.EDU>