Today I found something interesting. I've used overloading in the past without trouble but today wasn't getting stringification to work. I reduced my problem to the following test case:

package SomeClass;
use overload '""'=>"name";
sub new {
    return bless {}, shift;
}
sub name {
    my $self = shift;
    $self->{NAME} = shift if @_;
    return $self->{NAME};
}
1;

[download]

And here's my test script to use the class above:

use lib '.';
use SomeClass;
my $thing = SomeClass->new;
$thing->name('TestObj');
print "Explicit: my name is ", $thing->name, "\n";
print "Implicit: my name is $thing\n";
exit;

[download]

The second print statement printed "Implicit: my name is " whereas the first print worked as desired, including the name.

I tested the above under both 5.8.0 Linux-multi-thread and 5.8.0 MSWin-multi-thread and eventually came to realize that I could get it to work by pointing my overload directive to a third function in SomeClass:

sub stringify {
    my $self = shift;
    return $self->{NAME};
}

[download]

Any ideas why my first attempt failed? I can't see any good reason why my stringify() method works but not name(). Thanks in advance.

[Jon]

In reply to Overloading oddity by theguvnor

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