This code does not generate a warning under 5.6.1, so an easy answer would be to upgrade your version of Perl.

An other way is to use the /e option is the substitution:

$b =~ s/^(?:a(\w))?(\w)$/defined $1? "$1:$2" : ":$2"/e; <>The /e option evals the right part of the s/// operator, so you can test whether $1 is defined or not.

In reply to Re: Uninitialized $1 in s/// by mirod
in thread Uninitialized $1 in s/// by dmitri

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