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Javascript Regular Expressions
book

Javascript Regular Expressions

by Loiane Groner, Gabriel Manricks
May 2015
Intermediate to advanced
112 pages
2h 14m
English
Packt Publishing
Content preview from Javascript Regular Expressions

Defining nongreedy quantifiers

In the previous section, we had a look at multipliers, where you can specify that a pattern should be repeated a certain number of times. By default, JavaScript will try and match the largest number of characters possible, which means that it will be a greedy match. Let's say we have a pattern similar to /\d{1,4}/ that will match any text and has between one and four numbers. By default, if we use 124582948, it will return 1245, as it will take the maximum number of options (greedy approach). However, if we want, we can add the (?) question mark operator to tell JavaScript not to use greedy matching and instead return the minimum number of characters as possible:

Greedy matching is something that makes it difficult ...

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Publisher Resources

ISBN: 9781783282258