On Mar 11, 2007, at 5:30 PM, Per Bothner wrote:
* It improves consistency. Consider:
#|1|# (define VAR (MAC))
#|2|# (set! VAR (MAC))
#|3|# (list (MAC))
#|4|# (MAC)
#|5|# (define VAR (lambda () (MAC)))
#|6|# (set! VAR (lambda () (MAC)))
#|7|# (define-syntax MAC ...)
Which of #1-#6 are valid when followed by #7?
By my reading only #1 and #5 are allowed. But that doesn't seem
natural
to me. If #5 is allowed, then #6 should be allowed.
Similarly for #1 and #2.
Since #7 is a definition, it cannot come after an expression.
Consequently,
#2, #3, and #6 are not allowed after define-syntax, and this properly
has
nothing to do with whether expanding the body of a lambda is deferred
or not.
So, #1 and #5 are allowed because they are definitions and therefore can
appear with other definitions. The occurrence of MAC is a red herring
because the exact same answer can be given for:
#1# (define VAR 1)
#2# (set! VAR 1)
#3# (list 1)
#4# (MAC)
#5# (define VAR (lambda () 1))
#6# (set! VAR (lambda () 1))
#7# (define-syntax MAC ...)
Aziz,,,
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