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Regex explained: (...) # Match exactly 3 (the dots) characters and save them as a group (the parenthesis) .* # Match any character (the dot) 0 or more

• pyed 13y ago
  backreferencing is new to me, but why this: (...).*(...) isn't working !! ain't I back referencing the first group which is (...) ?
  • josso 13y ago
    It isn't working because (...) is just matching 3 characters. What your regex is saying, is basically: Match any 3 characters, then any character 0 or more times, then any 3 characters. You're reusing the regex and not the match. Back referencing essentially means that you'll match whatever is matched the first time, rather than reusing the regex pattern. I hope that made a little sense. Grouping, capturing, matching and backreferences is part of what makes regex tricky and very powerful. You might want to use some of the online tools, which can help explain the regex visually.
    • pyed 13y ago
      thanks for clearing that for me, I figured it out my self after giving it sometime.