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JavaScript Regular Expressions by Gabriel Manricks, Loiane Groner

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Defining custom quantifiers

There is only one syntax to specify your own multipliers but because of the different parameter options available, you get three different functional options.

If you want to match a given character a concrete number of times, you can simply specify the number of allowed repetitions inside curly braces. This doesn't make your patterns more flexible, but it will make them shorter to read. For example, if we were implementing a phone number we could type /\d\d\d-\d\d\d\d/. This is, however, a bit long and instead, we can just use custom multipliers and type /\d{3}-\d{4}/, which really shorten it up making it more readable.

Matching n or more occurrences

Next, if you just want to set a minimum number of times that the pattern ...

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