I looked at all the B::Lint documentation which O uses... and they look interesting and useful, just not for this. The dollar-underscore option doesn't handle writes to $_, while the implicit-write will complain about all writes to $_ - which, given that I want to write to $_ (without affecting the caller), will give me many false positives. Thanks, though - it's still quite interesting and informative.

In reply to Re^2: detecting changes in a localised variable by Tanktalus
in thread detecting changes in a localised variable by Tanktalus

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