Re: Me no understand scoping

[JonWilson <jsw@wilsonjc.us>]

Hi Andy,

Andy Wingo wrote:

> Do you see now why local-eval can't possibly work in the presence of
> efficient compilation? Scheme does not give you the particular kind of
> dynamism that you want. There is no hash table lurking inside a closure.

Why not compile most closures away, but leave those that are necessary
for the sort of semantics Maciek wants to work?  Maciek more or less
wants to reify environments (it seems), and have those be semantically
the same as the variable lookup mechanism inside closures.

It is certainly true that most continuations are not reified, many are
compiled away, but it is still possible to reify exactly the ones that
are needed and no others.  Is it impossible for program analysis to
reveal which environments need to be reified?  If necessary, one could
even require some sort of explicit tag on lambdas to say "This one gets
reified."

Of course, #scheme is probably a good place to discuss this sort of
thing, but I can't really hold my own once a really technical discussion
gets started there...  Whether that's because I lack the expertise
(likely) or because certain personalities are perhaps overly dominating
(also likely), I don't know.

Regards,
Jon