As TedYoung points out, while (<>) doesn't localize $_ and this is likely where it is getting clobberd.

<plug>Here's a short talk on the subject.</plug> Here are some interesting comments I got about it last time it was mentioned. (Especially Aristotle's surprising remark that no Perl construct implicitly localizes $_ at all!)

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

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