myoverload.pm

来自「source of perl for linux application,」· PM 代码 · 共 29 行

package Overloaded;

sub new {
    my $class = shift;
    bless { string => shift, num => shift }, $class;
}


package Overloaded::Compare;
use vars qw(@ISA);
@ISA = qw(Overloaded);

# Sometimes objects have only comparison ops overloaded and nothing else.
# For example, DateTime objects.
use overload
        q{eq}   => sub { $_[0]->{string} eq $_[1] },
        q{==}   => sub { $_[0]->{num}    == $_[1] };



package Overloaded::Ify;
use vars qw(@ISA);
@ISA = qw(Overloaded);

use overload
        q{""}    => sub { $_[0]->{string} },
        q{0+}    => sub { $_[0]->{num} };

1;