What is Regular Expressions, an Introduction to Regular Expressions

Regular expressions(or regex) are a language used for more sophisticated form and text processing. They are often used to perform complex search-and-replace operations, and to validate that text data is well-formed. Regular expressions can be used to perform all sorts of powerful text processing and manipulation in just about every language and on every platform. Every regular expression either matches text (search) or matches and replaces text (search and replace).

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