2.5: Regular Expressions: Back References - Programming with Text

In this short tutorial, I explain the concept of "back references" and explore how they are used to match the characters previously matched by capturing parentheses (groups) in a regular expression (regex).

This is the fifth video in a series on Regular Expressions, which is part of the "Programming from A to Z" course at ITP (http://itp.nyu.edu).

Next Video:    • 2.6: Regular Expressions: test() and match...  

http://shiffman.net/a2z/regex/

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Links discussed in this video:
MDN's Regular Expressions Reference: https://developer.mozilla.org/en/docs...
Regular Expressions on Wikipedia: https://en.wikipedia.org/wiki/Regular...
Book Mastering Regular Expressions: http://shop.oreilly.com/product/97805...
ITP from Tisch School of the Arts: https://tisch.nyu.edu/itp

Source Code for the all Video Lessons: https://github.com/CodingTrain/Rainbo...

p5.js: https://p5js.org/
Processing: https://processing.org

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