Monks, in my error messages, I strive to tell the users of my modules which argument has got something wrong with it and why. When I can't get perl to give me the error I want, I get mean. Can someone help me recover my happy feelings? 
use strict;
use warnings;

wants_foo_object({});

sub wants_foo_object {
    die "no object" unless defined(my $obj = shift);
    die "not an object" unless ref($obj);
    die "not a foo" unless $obj->isa('foo'); #the error I want
}

#The error I get: 
#C:\thomasdata\experiments>perl unblessedWantBetterError.t
#Can't call method "isa" on unblessed reference at unblessedWantBetter
+Error.t lin
#e 10.

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Edit g0n - retitled from "sub Wants_foo_object() wants a better error message (how to differentiate hash reference and object reference)"

In reply to How to differentiate hash reference and object reference? by tphyahoo

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