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It's a backreference to the first capture group, which is denoted by the first set of parenthesis, e.x. (.*)+\1 would match "ABAB", or "ABCABC", etc. "\2
by tlrobinson 12y ago
It's a backreference to the first capture group, which is denoted by the first set of parenthesis, e.x.
(.*)+\1
would match "ABAB", or "ABCABC", etc.
"\2" would match the second capture group, e.x.
(.*)(.*)\2\1
would match "ABBA", or "AABBBBAA", etc.
- Edmontonian 12y agoso in your first example, "AB" was in the capture group and the \1 repeats it?
- tlrobinson 12y agoCorrect. The following (.*)\1+ Would also match "ABABAB", for example.