On Fri, Apr 23, 2004 at 01:15:51PM -0400, Austin Hastings wrote:
: A12 sez:
:
: If your delegation object happens to be an array:
:
: has @:handlers handles 'foo';
:
: then something cool happens. <cool rays> In this case
: Perl 6 assumes that your array contains a list of potential
: handlers, and you just want to call the first one that
: succeeds.
:
: This is not clear, and I'm not liking it at the moment anyway. It has the
: effect of saying:
:
: "If you HAS-A attribute that is an array, you cannot delegate to it, but if
: you IS-A array, no worries."
:
: So Queue classes that start out:
:
: class Queue is Array {...}
:
: can get push/pop/splice whatever methods for free, but:
:
: class Queue is PersistentObject
: {
: has @:elements handles «push pop splice»;
:
: can not work (unless one of the things inside @:elements happens to be an
: array).
has $:elements handles «push pop splice»;
can hold an array in that case.
: Also, it's not clear:
:
: "first one that succeeds"
:
: Does that mean "First one for which a matching method exists" or does it
: mean "First one for which a method exists that does not C<fail> or return
: undef or some other badness"?
The latter is the intent.
Larry
