On Sun, Mar 11, 2007 at 01:13:13PM -0700, Per Bothner wrote:
> Scheme should allow expressions and declarations to be mixed in
> all bodies, not just top-level bodies.
I agree. I always tend to use macros that allow this, or if not, then
I just wrap everything inside a let* or letrec*.
There is a question of how this should be translated. If we have:
(let ()
(define a (foo))
(define b (bar))
(baz)
(define c (quux))
(quuux))
Then should it be translated as
(let ()
(letrec* ((a (foo))
(b (bar)))
(baz)
(letrec* ((c (quux)))
(quuux))))
or
(let ()
(letrec* ((a (foo))
(b (bar))
(dummy (baz))
(c (quux)))
(quuux)))
?
The first way would allow redefining the same variable multiple times
in a body, but I'd prefer the latter alternative, so that all
expressions and definitions directly inside a body use the same
scope. Moreover, I think that a definition should be allowed as the
final element of a body. The body of the resulting letrec* expression
would then be (unspecified).
Lauri
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