($res = $str) =~ s{ (\d+) }{ ($adj = $1) =~ s/(\d)/3/g; $adj }xe;

[download]

or 

($res = $str) =~ s{ (\d+) }{ $1 =~ s/(\d)/3/gr }xe;

[download]

In reply to Re: regex in REPLACEMENT in s/// by tybalt89
in thread regex in REPLACEMENT in s/// by perlboy_emeritus

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