Lesson 1
Introducing Regular Expressions
In this lesson you’ll learn what regular expressions are and what they can do for you.
Understanding the Need
Regular expressions (often shortened as RegEx or regex) are tools, and like all tools, regular expressions are designed to solve a very specific problem. The best way to understand regular expressions and what they do is to understand the problem they solve.
Consider the following scenarios:
You are searching for a file containing the text car
(regardless of case) but do not want to also locate car
in the middle of a word (for example, scar
, carry
, and incarcerate
).
You are generating a Web page ...
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