If you set this to just C<1>, the predicate is automatically named
C<has_${attr_name}> if your attribute's name does not start with an
-underscore, or <_has_${attr_name_without_the_underscore}> if it does.
+underscore, or C<_has_${attr_name_without_the_underscore}> if it does.
This feature comes from L<MooseX::AttributeShortcuts>.
=item * C<builder>