On Thu, 2004-05-13 at 15:35, Dov Wasserman wrote:
> [Special Property #1]
> If the Yada operator is valid anywhere a term is expected, it must
> syntactically valid in all these cases:
>
> my $id = ...;
Since I presume C<...> is going to be of type "Object" or whatever the
universal base class was (I think it was Object), this should compile
fine, and issue a run-time exception.
> my Int age = ...;
Same deal. There WOULD be a small difference with:
my int $age = ...;
which is actually:
my int $age = (...).prefix:+();
which is still valid, and produces a run-time exception.
> Therefore, the compile-time type of the term must be assignment-compatible
> with any and all lvalues.
Easy enough.
> [Special Property #2]
> As mentioned in A6, redefining a function (subroutine, method, etc.) which
> has only been declared with the Yada Yada Yada closure does not generate a
> warning. It seems like Perl 6 will have to take some special note, then,
> when we declare a function as:
>
> sub foo($bar, $baz) {...}; # pre-declaring sub foo()
Yes, that would have to be a special-case, and that means that ... is
smarter that just a macro (or perhaps that subroutine definition is
smarter than I'm giving it credit for. No biggie.
> [Question #1]
> I'd like to understand how Aaron Sherman's initial example would work:
>
> class Foo {
> has $.a;
> has $.b;
> ...;
> }
>
> We know that the class will compile fine, but when exactly would it pitch a
No we don't know that, but I think it's fair to say that class should
probably catch the Yadda exception, and define the metaclass with some
kind of property like "$thenewclass.meta does Exception::Yadda" or
something like that.
> [Question #2]
> Does C<...> know when it's being called during compilation and when it's
> being used at run-time? I.e., how would it behave in a compile-time block
> such as BEGIN:
>
> BEGIN { our IO $server = ...; };
No, I don't think it should know or care. BEGIN should probably
propagate the exception (or just ignore it), since there's no graceful
way to recover here.
> The rhs value is evaluated here at compile-time. Is C<...> smart enough to
> know that and keep quiet?
I don't see the value in "keeping it quiet". You've already executed the
code the one and only time you're going to, there's no sense in not
throwing the exception.
--
Aaron Sherman <[EMAIL PROTECTED]>
Senior Systems Engineer and Toolsmith
"It's the sound of a satellite saying, 'get me down!'" -Shriekback
