• PCRE regex
  • Introduction

  • Introduction
  • Introduction


    The syntax and semantics of the regular expressions
    supported by PCRE are described below. Regular expressions are also
    described in the Perl documentation and in a number of other books,
    some of which have copious examples. Jeffrey Friedl’s “Mastering
    Regular Expressions”, published by O’Reilly (ISBN 1-56592-257-3),
    covers them in great detail. The description here is intended as
    reference documentation.

    A regular expression is a pattern that is matched
    against a subject string from left to right. Most characters stand
    for themselves in a pattern, and match the corresponding characters
    in the subject. As a trivial example, the pattern The quick
    brown fox
    matches a portion of a subject string that is
    identical to itself.