! Aware to Perl: How can I catch accesses to undefined variables/functions/methods?

How can I catch accesses to undefined variables/functions/methods?

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The AUTOLOAD method, discussed in Autoloading and AUTOLOAD: Proxy Methods, lets you capture calls to undefined functions and methods.

When it comes to undefined variables that would trigger a warning under -w, you can use a handler to trap the pseudo-signal __WARN__ like this:

    $SIG{__WARN__} = sub {

        for ( $_[0] ) {

            /Use of uninitialized value/  && do {
                # promote warning to a fatal
                die $_;
            };

            # other warning cases to catch could go here;

            warn $_;
        }

};

Source: Perl FAQ: Perl Language Issues
Copyright: Copyright (c) 1997 Tom Christiansen and Nathan Torkington.

(Corrections, notes, and links courtesy of RocketAware.com)

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