a historical inquiry

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Date: Thu, 5 Feb 87 14:54 EST
From: Daniel L. Weinreb <DLW@ALDERAAN.SCRC.Symbolics.COM>
Subject: a historical inquiry
To: hplb29a!hplbgw!weeks@hplabs.HP.COM, common-lisp@SU-AI.ARPA
cc: hplbgw!weeks@hplabs.HP.COM
In-Reply-To: <8702051830.AA06435@hplbgw>
Message-ID: <870205145450.1.DLW@CHICOPEE.SCRC.Symbolics.COM>

    Date: Thu, 5 Feb 87 10:30:25 pst
    From: Gregory Weeks <hplb29a!hplbgw!weeks@hplabs.HP.COM>

    Could someone tell me what motivated people to include special variables in
    Common Lisp?  

(1) They're tremendously useful.  Nearly every major Lisp software
system I've ever used has used them to great advantage, and would suffer
significantly if they were not available.  Of course, the vast majority
of variables are lexical, but the few dynamic variables play important
roles.

(2) It was considered important to allow existing software to be
converted to Common Lisp in a relatively straightforward fashion.

		  Was there any dispute at the time?

No.  (In fact, at the time there was some debate about full lexical
scoping with upward and downward funargs; some people were dubious about
implementation issues.)