my $type_constraint = Stopwatch->meta->get_attribute('timer')->type_constraint;
print $type_constraint->name; # prints DateTime

##</code><code>##

print $type_constraint->parent->name; # prints Object
print $type_constraint->parent->parent->name; # prints Ref
print $type_constraint->parent->parent->parent->name; # prints Any

##</code><code>##

subtype Protocol
    => as Str
    => where { /^HTTP\/[0-9]\.[0-9]$/ };

##</code><code>##

has 'protocol' => (isa => 'Protocol');