Or you can create a dualvar using dualvar in core module Scalar::Util. Then, the returned value with be *both* a string and a number.

use Scalar::Util qw( dualvar );

sub sensible {
   return dualvar(1, "one");
}

my $foo = sensible();
print "Result = ", ''.$foo, "\n";   # Result = one
print "Result = ", 0+$foo,  "\n";   # Result = 1
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Very fast too. Nothing special as far as Perl is concerned.