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From: gjr@hplgr2.hpl.hp.com (Guillermo (Bill) J. Rozas)
Subject: Re: R5RS?
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In-Reply-To: ziggy@biere.ai.mit.edu's message of 14 Mar 1996 01:38:14 GMT
Date: Thu, 14 Mar 1996 19:20:33 GMT
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In article <ZIGGY.96Mar13203815@biere.ai.mit.edu> ziggy@biere.ai.mit.edu (Michael R. Blair) writes:

|    does it mean that once I have used DEFINE once to redefine READ
|    at the top-level, thereafter READ has been ``redefined'' so it is
|    now permitted to use SET! to re-bind it repeatedly thereafter
|    using SET! (taking ``unless'' to mean ``until after'')?

I believe this was the intended interpretation.

In other words

(define read ...)
(set! read ...)

is legal, while just

(set! read ...)

is illegal in compliant (i.e. portable) programs.
