[perl #126111] [BUG] coercive type constraint for variable inconsistently accepted

[Aleks-Daniel Jakimenko-Aleksejev via RT]

Still reproducible (2017.11,HEAD(e5b660e))

On 2015-09-19 11:15:43, zef...@fysh.org wrote:
> A coercive type constraint is not permitted on a variable:
>
> $ ./perl6 -e 'my Int() $a; say 1'
> ===SORRY!=== Error while compiling -e
> Coercion Int(Any) is insufficiently type-like to qualify a variable
> at -e:1
> ------> my Int() $a^; say 1
> expecting any of:
> constraint
>
> But it *is* accepted if expressed in "of" form:
>
> $ ./perl6 -e 'my $a of Int(); say 1'
> 1
>
> But it doesn't actually work:
>
> $ ./perl6 -e 'my $a of Int(); $a = 3; say $a'
> Type check failed in assignment to '$a'; expected 'Int(Any)' but got 'Int'
> in block <unit> at -e:1
>
> Presumably it should be forbidden in the "of" form just as it is forbidden
> in the prefix form.
>
> -zefram