Re: lexical scope and dynamic extent

["Rodney A. Brooks" <BROOKS%MIT-OZ@MIT-MC.ARPA>]

In Lucid's SUN Common Lisp 1.0, compiled foo, you get

>>Error: A go to one of (L) occured from within an out of scope closure

Maybe the English needs a little work...

    Date: Wed, 27 Nov 85 18:31:55 pst
    From: mips!escargot.earl@glacier (Earl Killian)
    Message-Id: <8511280231.AA15071@escargot.UUCP>
    To: common-lisp@su-ai.ARPA
    Subject: lexical scope and dynamic extent

    Some entities in the language are described as having lexical scope
    and dynamic extent, which means that they can be refered to after
    they're gone.  Do any of the implementations have good ways of
    detecting such things?  Here's a nasty one:

    (defun foo ()
      (tagbody
        l (return-from foo #'(lambda () (go l)))))
    (funcall (foo))

    If you type this at various implementations, what do you get?
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