Given a reference to a subroutine, how would you go about checking the that referenced subroutine actually exists.

For example if I run

perl -e'print \&not_there'

I get back the reference CODE(0xeb570) which _looks_ like a valid subroutine reference, but (of course) isn't as the subroutine it claims to reference doesn't exist.

I suppose you can find out by running the reference in an 'eval' block, but you might not want to do that if the subroutine has potentially dangerous side effects.

--
<http://www.dave.org.uk>

European Perl Conference - Sept 22/24 2000, ICA, London
<http://www.yapc.org/Europe/>

In reply to Validating a Code Reference by davorg

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