Whilst trying to explain to someone the benefits of

eval { $x->isa( $class ) }

to determine if an object belongs in a class, I embarrassingly came across the following behavior, which I could not explain.

use strict;
use warnings;

my $x = 'string';
$x->isa('huh?');

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This, surprisingly, runs without error. If instead, I make $x a number: 
use strict;
use warnings;

my $x = 3;
$x->isa('huh?')

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I get the expected error: 
Can't call method "isa" without a package or object reference at foo.pl line 5.
Why should a string have access to UNIVERSAL methods while a number doesn't? I've tried this with Perl 5.10.1 and 5.12.2.

In reply to strings->can->isa but numbers->can't? by djerius

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