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What are Regular Expressions (aka. Regexes)?

  • An idea on how to match some pattern in some text.
  • A tool/language that is available in many places.
  • Has many different "dialects"
  • Has many different modes of processing.
  • The grand concept is the same.
  • Uses the following symbols:
() [] {} . * + ? ^ $ | - \ \d \s \w \A \Z \1 \2 \3