Hi

I'm trying to work out how/why one might overload '0+' ... and I'm not having much success. 
use warnings;
use strict;

package Soldier;

use overload '0+' => \&truncate;

my $soldier1 = {NAME   => 'BENJAMIN',
                RANK   => 'PRIVATE' ,
                SERIAL =>    151.11};

bless $soldier1;

my $int = int($soldier1);
print $int, "\n";

sub truncate {
    print "sub truncate called: ", int($_[0]->{SERIAL}), "\n";
    return int($_[0]->{SERIAL});
}

__END__

OUTPUTS:
sub truncate called: 151
sub truncate called: 151
151

[download]
Questions:
1) Why does the sub truncate get called twice ?
2) Why would one want to overload the int() function with use overload '0+' => \&truncate; when use overload 'int' => \&truncate; works just as well (and gets called only once when substituted into the above demo script) ?
3) I notice that $soldier1 ? 1 : 0; also calls truncate (just once). I don't know why that is. Under what other circumstances will sub truncate be called ?

Perhaps I just need to see a proper example of the usage of overloading '0+'.

Cheers,
Rob

In reply to overloading '0+' by syphilis

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