For a lighter solution, just use a (built-in) dualvar: 
use Scalar::Util 'dualvar';

my $funny = dualvar 12, 'pancake';

printf "Polly wanna %s every %d days \n", $funny, $funny;
printf "Polly wanna %s every %d days \n", $funny, 0+$funny;

__END__

[download]
Or, if you really do want a full object-based solution, Contextual::Return can do the hard work (of setting up the class and overloading) for you: 
use Contextual::Return;

my $funny = NUM { 12 }
            STR { 'pancake' };

printf "Polly wanna %s every %d days \n", $funny, $funny;
printf "Polly wanna %s every %d days \n", $funny, 0+$funny;

__END__

[download]
But, if you just want number and string, a dualvar is probably the better choice.

In reply to Re: User variables with two values? by DamianConway
in thread User variables with two values? by Anonymous Monk

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