On Sun, Aug 31, 2014 at 04:13:03PM -0400, Lincoln A Baxter wrote:
> Sys::SigAction has one instance of a call to UNIVERSAL::isa (line 135 of
> SigAction.pm) in a function context:
>
> die '$action is not a POSIX::SigAction' if not UNIVERSAL::isa( $action
> ,'POSIX::SigAction' );
>
> This call is in set_sigaction() which is in a private function and it is
> essentially just defensive programming. I don't think I have had a
> problem with this since is was first released. The reason
> UNIVERSAL::isa is called as a function here is that that within the
> scope of this function how might one know if the scaler $action is
> blessed reference, just a reference, or something else. UNIVERSAL::isa()
> answers all of these questions in one statement.
>
> If UNIVERSAL::isa() is now deemed "incorrect" in a context like this,
> I'm curious, given the requirements this line of code meets, what those
> on this list think this line of code should be converted to.
... if not (blessed($action) and $action->isa('POSIX::SigAction'))
...which is a little longer, so exactly why Safe::Isa was written :)
(note: I'm not the author, just the most recent releaser)
