"These variables keep their value until a new regex is successfully matched or dynamic scope is exited."

I'm not sure that is true. I remember a node that fairly recently talked about this, but I couldn't find it, only What's happening to my $1?.

What I remember is that a failed match could in some circumstances modify $1. So $1 is only reliable if the match succeeds (can't rely upon it being what it was after the previous regex after a failed match). I also remember that this behavior is Perl version specific.

I haven't run across this in my code as I do whatever I'm going to do with $1 right after the regex and have never written code that decides whether $1 changed or not. I only use $1 if the match succeeded.

Yes, this is a nit, but Perl Monks is good about resolving these nits and details.

In reply to Re^3: Use of uninitialized value $1 by Marshall
in thread Use of uninitialized value $1 by Pazitiff

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