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SHAY / perl-5.40.1 / lib / overloading.pm 

            

              
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package overloading;
use warnings;
our $VERSION = '0.02';
my $HINT_NO_AMAGIC = 0x01000000; # see perl.h
require 5.010001;
sub _ops_to_nums {
    require overload::numbers;
    map { exists $overload::numbers::names{"($_"}
        ? $overload::numbers::names{"($_"}
        : do { require Carp; Carp::croak("'$_' is not a valid overload") }
    } @_;
}
sub import {
    my ( $class, @ops ) = @_;
    if ( @ops ) {
        if ( $^H{overloading} ) {
            vec($^H{overloading} , $_, 1) = 0 for _ops_to_nums(@ops);
        }
        if ( $^H{overloading} !~ /[^\0]/ ) {
            delete $^H{overloading};
            $^H &= ~$HINT_NO_AMAGIC;
        }
    } else {
        delete $^H{overloading};
        $^H &= ~$HINT_NO_AMAGIC;
    }
}
sub unimport {
    my ( $class, @ops ) = @_;
    if ( exists $^H{overloading} or not $^H & $HINT_NO_AMAGIC ) {
        if ( @ops ) {
            vec($^H{overloading} ||= '', $_, 1) = 1 for _ops_to_nums(@ops);
        } else {
            delete $^H{overloading};
        }
    }
    $^H |= $HINT_NO_AMAGIC;
}
1;
__END__
=head1 NAME
overloading - perl pragma to lexically control overloading
=head1 SYNOPSIS
    {
        no overloading;
        my $str = "$object"; # doesn't call stringification overload
    }
    # it's lexical, so this stringifies:
    warn "$object";
    # it can be enabled per op
    no overloading qw("");
    warn "$object";
    # and also reenabled
    use overloading;
=head1 DESCRIPTION
This pragma allows you to lexically disable or enable overloading.
=over 6
=item C<no overloading>
Disables overloading entirely in the current lexical scope.
=item C<no overloading @ops>
Disables only specific overloads in the current lexical scope.
=item C<use overloading>
Reenables overloading in the current lexical scope.
=item C<use overloading @ops>
Reenables overloading only for specific ops in the current lexical scope.
=back
=cut