On Thu, 08 Oct 2015 03:12:02 -0700, ilmari wrote:
> Or to put another way: attributes with 'is required' should not need
> an
> initialiser even if the type has a :D smiley, and a :D type without an
> initialiser should imply 'is required'.
>
> The first and second examples below should be equivalent.
>
> > class { has Int:D $.count }.new(count => 42)
> ===SORRY!=== Error while compiling <unknown file>
> Variable definition of type Int:D requires an initializer
> at <unknown file>:1
>
> > class { has Int:D $.count is required = Int }.new(count => 42)
> <anon>.new(count => 42)
>
>
> And the error message should probably be this:
>
> > class { has Int $.count is required }.new()
> The attribute '$!count' is required, but you did not provide a value
> for it.
> in block <unit> at <unknown file>:1
>
> Rather than this:
>
> > class { has Int:D $.count is required = Int }.new()
> Type check failed in assignment to $!count; expected Int:D but got Int
> in block <unit> at <unknown file>:1
On Thu, 08 Oct 2015 07:34:43 -0700, FROGGS.de wrote:
> I don't think that we should mix two concepts here.
Agreed. Especially since `is default` trait can be used, making the cases where
implied `is required` trait would make sense even more narrow.
It's possible the user intended to "accept only definite values" without
realizing
the default default of the attribute would not pass the type constraint.
Silently
making the attribute required would just add more to the confusion.
> Rather than this:
>
> > class { has Int:D $.count is required = Int }.new()
> Type check failed in assignment to $!count; expected Int:D but got Int
> in block <unit> at <unknown file>:1
Exactly that (required + default) should actually throw, the same as it does
with
parameters in routines. I opened a separate Issue for that:
https://github.com/rakudo/rakudo/issues/1426
Without the default, the error is (and was, when issue was opened) the same for
:D and :_ types
