On Mon, Jun 11, 2012 at 7:57 AM, Per Bothner <[email protected]> wrote:

> In Kawa:
>
> Implicit forcing happens for:
> ...
>

  I agree that making a promise with an immediate value could evaluate to
that immediate instead of creating a promise. But in general I think that a
promise have to be opaque until forced and that it is worth to have a
disjoint type for promises and to be able to check if an object is a
promise or not.  IMHO for any other usage auto-forcing in primitives
strongly sounds as being in the "it seems a good idea at that time"
department: auto-forcing means that primitives have to check if something
is a promise and forcing it in that case, adding this check add a cost and
it has deep impact on the language semantics.

--
Emmanuel
_______________________________________________
Scheme-reports mailing list
[email protected]
http://lists.scheme-reports.org/cgi-bin/mailman/listinfo/scheme-reports

Reply via email to