As of Perl 5.7.0 this behaviour has changed for $1 and friends. From perl570delta:

The regular expression captured submatches ($1, $2, ...) are now more consistently unset if the match fails, instead of leaving false data lying around in them.

ihb

Read argumentation in its context!

In reply to Re^2: You *Can* Catch errors in closing lexical filehandles by ihb
in thread Catching errors in closing lexical filehandles by gaal

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