Or using the nicer-looking use base. It will complain that the Bar package is empty, so I put a sub in it, but then it works fine. 
my $foo = Foo->new;
print "foo is".($foo->isa( 'Bar' ) ? '' : ' _not_')." a Bar\n";

package Bar;
sub null {}

package Foo;
use base Bar;
sub new { bless {},shift }

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In reply to Re: Re: Foo is not a Bar, why? by Mr_Person
in thread Foo is not a Bar, why? by liz

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