# New Ticket Created by Zefram
# Please include the string: [perl #126906]
# in the subject line of all future correspondence about this issue.
# <URL: https://rt.perl.org/Ticket/Display.html?id=126906 >
If a defined value is used as a type constraint, the values that the
constraint will accept are inconsistent between using the type constraint
on a variable and using it on a sub parameter:
> constant T = 3
3
> 3.^isa(T)
0
> (sub (T $a) { 1 })(3)
1
> my T $a = 3
Type check failed in assignment to $a; expected 3 but got 3
in block <unit> at <unknown file>:1
The two type constraint situations are consistent in disallowing other
values such as 2, "foo", and Int. It probably should not be permitted
at all to use anything other than a type object as a type constraint.
See also [perl #126117].
-zefram
