This could be explained if  $_ had been assigned a defined value by some operation previous to the code shown in the OP.

The other twist I noticed is that the regex is really  /\Z/ and not  /\\Z/. The former regex matches everything, even undef (although a warning is still generated for a match against undef if warnings are enabled).

In reply to Re^3: Regex returns match the first time. It returns everything thereafter by AnomalousMonk
in thread Regex returns match the first time. It returns everything thereafter by guitarplayer68

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