When Regular Expressions Are (or Aren’t) the Right Parsing Tool

An old adage says, “When the only tool you have is a hammer, all problems will look like nails.” This saying definitely applies to regular expressions. While regular expressions are a very powerful tool, it is important to remember that they are not the only tool at your disposal. This section explores the most likely reasons that you may want to use some of the simpler parsing methods mentioned in Chapter 4.

Strengths of Regular Expressions

If you can abstract the content you want to extract, or parse, with an alphanumeric pattern, then you probably should be using regular expressions. Regular expressions are an extraordinarily powerful tool because much of the data we want to scrape ...

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