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From: jeff@aiai.ed.ac.uk (Jeff Dalton)
Newsgroups: comp.lang.functional
Subject: Re: Is Lisp in class X?
Message-ID: <2632@skye.ed.ac.uk>
Date: 3 Jun 90 17:10:00 GMT
References: <14810@dime.cs.umass.edu>
Reply-To: jeff@aiai.UUCP (Jeff Dalton)
Organization: AIAI, University of Edinburgh, Scotland
Lines: 36

In article <14810@dime.cs.umass.edu> pop@cs.umass.edu () writes:
>I would say that most Lisps fall short of being in X because they do not
>provide a proper treatment of function variables i.e.  you cannot say
>(F X1 .... XN)  where  F is a variable - you have to do some funny
>circumlocution which I don't remember. 

Another in the Traditional Complaints series ("Collect them all!").

Since this has already been debated, at length, in Comp.lang.lisp,
let me just say that opinions differ as to how significant it is
that in some Lisps the syntax for calling function values (it's
any function-valued expression, not just variables) is something
like (funcall f x1 ... xn) or (apply* f x1 ... xn) rather than
just (f x1 ... xn).

>The binding of functions to function names in LISP is of a different
>nature from variable bindings.

One could just as well say they have the same nature but happen to
be independent.

>Scheme, somewhat tardily, provides a LISP dialect that gets it right.

Tardily, i.e., in 1975.

Lisp 1.5, which also lets you write (F ...), goes back at least to
1962.

>one of the reasons that Edinburgh got it right earlier (POP-2 -> Hope -> ML)

I would not say Pop got it right, because (1) variables in Pop have
dynamic scope and (2) closures have to have an explicit annotation
listing the variables to close over [cf FUNCTION in Lisp 1.5].  I
regard these as more significant defects.

-- Jeff