use Perl

I didn't mean to critique your post. I actually *just* ran into an undef warning being tossed by someone else's module. It was harmless, so I tried to use your code to catch it. Quite a coincidence.

Brain stopped working for a moment. Just remembered it's $SIG{__WARN__}.

Does this work? I get an error:

  $ perl -Mwarnings -e'$SIG{WARN}=sub{}; my $a; my $b=$a+1;'
  No such signal: SIGWARN at -e line 1.
  Use of uninitialized value $a in addition (+) at -e line 1.