On Tue, Aug 08, 2006 at 11:35:30 +0000, Luke Palmer wrote:
> On 8/8/06, Yuval Kogman <[EMAIL PROTECTED]> wrote:
> >I personally prefer delegates for almost any design dillema, but
> >most CPAN modules aren't that way.
> Well, what way are they?

Usually not polymorphic at all.

We have the capabilities to do very flexible polymorphism with
delegation today. Roles aren't necessary from a purist perspective,
they just make it much easier to do very flexible polymorphism more
often since it'll be easier.

> How else has this problem been solved?

I dunno...

> If a function declares a
> parameter as a SomeAPI and then passes it on to a helper function,
> which leaves it untyped, which then calls header, what happens?
> Since your proposal is lexical, SomeOtherAPI's is called, which is
> probably not what was intended.

My original idea was that this is again an ambiguity error - without
the helper function stating which role it's using it cannot dispatch
the "header" method at all, since it's in a role-conflicted state.

  Yuval Kogman <[EMAIL PROTECTED]>
http://nothingmuch.woobling.org  0xEBD27418

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