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EXODIST / Test-Simple-1.302210 / lib / Test2 / Compare / Negatable.pm 

            

              
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package Test2::Compare::Negatable;
use strict;
use warnings;
our $VERSION = '1.302210';
require overload;
require Test2::Util::HashBase;
sub import {
    my ($pkg, $file, $line) = caller;
    my $sub = eval <<"    EOT" or die $@;
package $pkg;
#line $line "$file"
sub { overload->import('!' => 'clone_negate', fallback => 1); Test2::Util::HashBase->import('negate')}
    EOT
    $sub->();
    no strict 'refs';
    *{"$pkg\::clone_negate"} = \&clone_negate;
    *{"$pkg\::toggle_negate"} = \&toggle_negate;
}
sub clone_negate {
    my $self = shift;
    my $clone = $self->clone;
    $clone->toggle_negate;
    return $clone;
}
sub toggle_negate {
    my $self = shift;
    $self->set_negate($self->negate ? 0 : 1);
}
1;
__END__
=pod
=encoding UTF-8
=head1 NAME
Test2::Compare::Negatable - Poor mans 'role' for compare objects that can be negated.
=head1 DESCRIPTION
Using this package inside an L<Test2::Compare::Base> subclass will overload
C<!$obj> and import C<clone_negate()> and C<toggle_negate()>.
=head1 WHY?
Until perl 5.18 the 'fallback' parameter to L<overload> would not be inherited,
so we cannot use inheritance for the behavior we actually want. This module
works around the problem by emulating the C<use overload> call we want for each
consumer class.
=head1 ATTRIBUTES
=over 4
=item $bool = $obj->negate
=item $obj->set_negate($bool)
=item $attr = NEGATE()
The NEGATE attribute will be added via L<Test2::Util::HashBase>.
=back
=head1 METHODS
=over 4
=item $clone = $obj->clone_negate()
Create a shallow copy of the object, and call C<toggle_negate> on it.
=item $obj->toggle_negate()
Toggle the negate attribute. If the attribute was on it will now be off, if it
was off it will now be on.
=back
=head1 SOURCE
The source code repository for Test2-Suite can be found at
F<https://github.com/Test-More/test-more/>.
=head1 MAINTAINERS
=over 4
=item Chad Granum E<lt>exodist@cpan.orgE<gt>
=back
=head1 AUTHORS
=over 4
=item Chad Granum E<lt>exodist@cpan.orgE<gt>
=back
=head1 COPYRIGHT
Copyright Chad Granum E<lt>exodist@cpan.orgE<gt>.
This program is free software; you can redistribute it and/or
modify it under the same terms as Perl itself.
See F<http://dev.perl.org/licenses/>
=cut