Re^2: Lookahead regex help

That seems to work. Thanks. But I am curious as to what the \2 does?

Comment on Re^2: Lookahead regex help

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Re^3: Lookahead regex help by borisz (Canon) on Aug 16, 2004 at 16:37 UTC
\2 looks for what the second () pair has captured. In this case a single char. Boris	[reply]
Re^3: Lookahead regex help by Anonymous Monk on Aug 17, 2004 at 02:25 UTC
$$ perl -MYAPE::Regex::Explain -e'die YAPE::Regex::Explain->new(qr/((. +)\2)/i)->explain' The regular expression: (?i-msx:((.)\2)) matches as follows: NODE EXPLANATION ---------------------------------------------------------------------- (?i-msx: group, but do not capture (case-insensitive) (with ^ and $ matching normally) (with . not matching \n) (matching whitespace and # normally): ---------------------------------------------------------------------- ( group and capture to \1: ---------------------------------------------------------------------- ( group and capture to \2: ---------------------------------------------------------------------- . any character except \n ---------------------------------------------------------------------- ) end of \2 ---------------------------------------------------------------------- \2* what was matched by capture \2 (0 or more times (matching the most amount possible)) ---------------------------------------------------------------------- ) end of \1 ---------------------------------------------------------------------- ) end of grouping ---------------------------------------------------------------------- [download]	[reply] [d/l]