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Re: where is srfi-17 going?

This page is part of the web mail archives of SRFI 17 from before July 7th, 2015. The new archives for SRFI 17 contain all messages, not just those from before July 7th, 2015.

>>>>> "David" == David Rush <kumo@xxxxxxxxxxxxx> writes:

David> Yes. And I must admit that in these terms I find this proposal
David> somewhat seductive. However, Per's analogy with the C `&' operator
David> makes very clear how big this issue is. SRFI-17 is tinkering with
David> fundamental language semantics. How does adding *explicit* pointer
David> types and the accompanying pointer-aliasing problems interact with the
David> compiled Schemes? Or how they interact with the garbage collector?

David> Now, I am not totally opposed to this idea, but I rather like
David> the way that things currently work in Scheme. The proposed model of
David> L-values actually seems remarkably close to SML's ref type (which I
David> like), but with an important difference: In Scheme (AFAIU) *all* names
David> are bound to values of ref type, whereas in SML only those names which
David> are explicitly declared to be so are. Scheme includes some magic so
David> that all values of ref type are automatically dereferenced, *except*
David> in the case of SET!. SET-CAR! & friends don't even enter into the
David> picture, they are simply operations on opaque types following the
David> usual Scheme rules.

You might want to check out:

Michael Sperber, Peter Thiemann:
ML and the Address Operator
Proceedings of the 1998 ACM SIGPLAN Workshop on ML
Pages 4--13

The paper addresses pretty much all of these issues.  I'll send
PostScript to anyone who's interested.

Cheers =8-} Mike
Friede, Völkerverständigung und überhaupt blabla