March 2001
Intermediate to advanced
400 pages
8h 35m
English
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8.1. The Role of Regular Expressions
Regular expressions appear frequently in support of user interfaces. For example, a user might want to see all the files that end with ".txt" or all the books whose titles include "Java" and "Parsers". When you allow a user to specify such a pattern, you are using regular expressions to let the user create a new little language. You might decide, for example, to allow your user to use a tilde to mean zero or more characters. If your user types "~.txt", he or she is defining the language of all strings that end with ".txt".
The tools you provide your user for matching are a metalanguage, a language for defining new languages. Typically, developers provide users with symbols such as “~” and “|” to indicate which ...
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.