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Re: lexical scope and dynamic extent
- To: mips!escargot.earl@SU-GLACIER.ARPA, common-lisp@SU-AI.ARPA
- Subject: Re: lexical scope and dynamic extent
- From: Richard Acuff <Acuff@SUMEX-AIM.ARPA>
- Date: Thu 28 Nov 85 10:51:07-PST
- In-reply-to: <8511280231.AA15071@escargot.UUCP>
In Explorer Common Lisp you get:
>>>ERROR: GO tag L is not defined or is no longer valid
which seems reasonable given the statment near the top of pg. 131 of
CLtL, "Once a tagbody construct has been exited, it is no longer legal
to go to a tag in its body."
I think you may be confusing dynamic extent and indefinite extent.
An entity with dynamic extent (in this case the tag) continues to
exist only as long as the form that establishes it (the tagbody),
while entities with indefinite extent continue to exist as long as
there is a reference to them.