package Stringify;

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

# Time passes
package Fu;
*toString = Stringify::objectToString("Fu");

##</code><code>##

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;

##</code><code>##

package Fu;
use Stringify; # Use objects as strings, and they stringify