Thank you all for your answers!

Well then... I think I'll 'switch' to 
$is_my_class = defined($object) && $object->isa('My::Class');

[download]
since I used to write 
$is_my_class = defined($object) && $UNNIVERSAL::isa($object, 'My::Clas
+s');

[download]
or 
$is_my_class = eval { $fd->isa('My::Class') };

[download]
to preserve my keyboard! ;)

@ Tanktalus: uh... I've never thought about this. But I think I... yeah... the time will come when I'll have to write a Decorator! At least this came to my mind when I read your post.

k

In reply to Re: Do not use UNIVERSAL::isa this way; but why? by klekker
in thread Do not use UNIVERSAL::isa this way; but why? by klekker

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