Wrong behavior of the implicit smart operator in the given/when blocks

[Anonymous Monk]

I have the following code:

use 5.010;

my %hash = (a => 1);

given(\%hash){           # first true
#given('a'){             # all true
    when('a' ~~ $_){
        say "explicit ~~";
        continue;
    }
    when($_ ~~ 'a'){
        say "reversed explicit ~~";
        continue;
    }
    when('a'){
        say "implicit ~~";
    }
}

It is known that 'key' ~~ \%hash returns true if 'key' exists in %hash.

From the above code, when('a'){...} should return true because the key 'a' exists in %hash.

I see this as a perl bug. - Please correct me if I'm wrong.

My solution is when('a'){...} to be equivalent with when('a' ~~ $_){...}.
(In perl v5.14.2, it is equivalent with when($_ ~~ 'a'){...} - which in this case is wrong