If you're going to call the sub anyway, call it in an eval and see what happens. If some other error comes up, you can rethrow it with die. 

eval { &$sub };
if ( $@ =~ /^Undefined subroutine/ ) {
    # This is what happens when you call a bogus sub ref.
}
elsif ( $@ ) {
    die $@;
}

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In reply to Re: How do I test the validity of a CODE reference? by kyle
in thread How do I test the validity of a CODE reference? by pilap

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