Jeffrey Friedl's Mastering Regular Expressions is really an authority on the subject. It is a O' Reilly book. Not entirely sure, though, that it is the best for a pure beginner. I *think* that it can be downloaded for free (in due respect of the law, that is), but am not entirely sure.

In reply to Re^5: Using Regex to extract variable-length substring by Laurent_R
in thread Using Regex to extract variable-length substring by Anonymous Monk

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