use Number::Fraction;
package Number::Fraction::Foo;
use base qw/Number::Fraction/;
1;
package Number::Fraction::Bar;
use base qw/Number::Fraction/;
1;

my $n=Number::Fraction->new(1,4);
my $f=Number::Fraction::Foo->new(1,4);
my $b=Number::Fraction::Bar->new(1,4);

print $n+$f,$/;
print $n+$b,$/;
print $f+$n,$/;
print $b+$n,$/;
print $f+$b,$/;
print $b+$f,$/;
__END__
Can't add a Number::Fraction::Foo to a Number::Fraction::Foo at D:\perl\devlib\/Number/Fraction.pm line 119
	Number::Fraction::add('1/4', '1/4', '') called at D:\Temp\nf.pl line 15
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##</code><code>##

use Number::FractionP;
package Number::FractionP::Foo;
use base qw/Number::FractionP/;
1;
package Number::FractionP::Bar;
use base qw/Number::FractionP/;
1;

my $n=Number::FractionP->new(1,4);
my $f=Number::FractionP::Foo->new(1,4);
my $b=Number::FractionP::Bar->new(1,4);

print $n+$f,$/;
print $n+$b,$/;
print $f+$n,$/;
print $b+$n,$/;
print $f+$b,$/;
print $b+$f,$/;

__END__
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