Rate    eval2 blessed1    eval1 blessed2
eval2    6.80/s       --     -57%     -61%     -76%
blessed1 15.9/s     134%       --      -9%     -43%
eval1    17.4/s     156%      10%       --     -38%
blessed2 28.0/s     313%      76%      61%       --

##</code><code>##

#!/usr/bin/perl
use strict;
use warnings;

use Scalar::Util qw( blessed );
use Benchmark qw( cmpthese );

my $obj = bless {}, 'Foo';
my $not_obj;
my $result;

cmpthese( -1, {
    eval1 => sub { 
        for ( 0 .. 10_000 ) {
            $result = eval { $obj->isa('Foo') };
            $result = eval { $obj->isa('Bar') };
        }       
    },
    blessed1 => sub {
        for ( 0 .. 10_000 ) {
            $result = blessed($obj) and $obj->isa('Foo');
            $result = blessed($obj) and $obj->isa('Bar');
        }       
    },
    eval2 => sub {
        for ( 0 .. 10_000 ) {
            $result = eval { $not_obj->isa('Foo') };
            $result = eval { $not_obj->isa('Bar') };
        }       
    },
    blessed2 => sub {
        for ( 0 .. 10_000 ) {
            $result = blessed($not_obj) and $not_obj->isa('Foo');
            $result = blessed($not_obj) and $not_obj->isa('Bar');
        }       
    },
});