Suppose you wanted to do something like this to a family of related objects. How would you assign the anonymous function to be a method of each class? (I can do that trick in JavaScript using ObjectName.prototpye.methodName, but how would I do that in Perl?)

For example, what I would like to do is:

...
sub ObjectToString {
    my $name = shift;
    return sub {
        my $s = $name . $self->getParametersAndValues();
        return $s;
    }
}
...
package Fu;
sub toString = ObjectToString("Fu");
...
package Bar;
sub toString = ObjectToString("Bar");
...
package Baz;
sub toString = ObjectToString("Baz");
...
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Then I would use it like this:

my ($foo, $bar, $baz);

$foo = Fu->new();
# do stuff with foo...
print $foo->toString();

$bar = Bar->new();
# do stuff with bar...
print $bar->toString();
...
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The obvious answer here is to use Inheritance™, but what if, for some reason, I don't want to use inheritance? Can I still accomplish what I want to?

You would want to do a typeglob assignment. If you assign an anonymous function to a typeglob, you define that function. Like this:

package Stringify;

sub objectToString {
  my $name = shift;
  return sub {
    $name . (shift)->getParametersAndValues();
  };
}

# Time passes
package Fu;
*toString = Stringify::objectToString("Fu");
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But I should note that you can make this nicer with overload and an autogenerated method. For instance:

package Stringify;
use strict;
use Carp;

sub import {
  my $pkg = caller();
  my $code = qq(
    # A trick for custom error reporting - see perlsyn.
    \n# line 1 "'Autogenerated for $pkg by Stringify'"
    package $pkg;
    use overload '""' => sub {
      __PACKAGE__ . (shift)->getParametersAndValues();
    };
  );
  eval($code);
  if ($@) {
    confess("Cannot autogenerate stringification for package '$pkg': $
+@
      The code is:\n$code");
  }
}

1;
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would allow you to simply:

package Fu;
use Stringify; # Use objects as strings, and they stringify
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If you want you could create an autogenerated function called toString and pass a reference to that function to overload.

You know what happened, don't you? Just as I was leaving the building, not more than five minutes after I asked the question, the answer came to me: symbol table. :-)

The import approach is interesting. It gives me more food for thought, especially in relation to this question I asked about writing your own import. Thanks.