If I am doing some kind of subscript computation and my subscript happens to go negative, I want to know about it (by receiving undef) NOW
How about 
my $i = ... some calculation ...
if ( $i >= 0 ) {
  $val = $tiedArray[$i];
}
else {
  # report the problem!
}

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In reply to Re: index wrapping in tied FETCH and EXISTS by apl
in thread index wrapping in tied FETCH and EXISTS by cmac

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