以下代码无法按预期方式工作.我错过了什么？
use strict;
use warnings;
use overload '|' => sub { 1 / ( 1 / $_[0] + 1 / $_[1] ) };
print( 5 | 5 ); # Prints '5' instead of '2.5'
解决方法
过载仅适用于有福的引用(“对象”).
package MyNumber;
use strict;
use warnings;
use overload '|' => sub { 1 / ( 1 / +$_[0] + 1 / +$_[1] ) },'0+' => sub { $_[0]->{value} },# Cast to number
fallback => 1; # Allow fallback conversions
# "Constructor",bless number as MyNumber
sub num {
my $self = { value => $_[0] }; # can be any reference
return bless $self,"MyNumber";
}
print(num(5) | num(5));
my $a = num(5);
print ($a | 5); # This works too