JavaScript RegExp – p{N}

When it comes to working with strings in JavaScript, regular expressions (or regex) are a powerful tool to have in your toolkit. They allow you to search, replace and manipulate strings in a variety of ways. One of the often overlooked features of regex in JavaScript is the p{N} property. In this article, we’ll explore how to use p{N} in our regular expressions.

What is p{N}?

p{N} is a Unicode property. Unicode is a standard that assigns a unique number to every character in every writing system in the world. It also provides a way to represent and work with these characters in computer programs. Unicode properties refer to specific groups of characters based on some shared characteristic.

p{N} is one of the Unicode properties that refers to characters that are numerals. It matches any character that is a number like 0, 1, 2, 3, 4, 5, 6, 7, 8 or 9. It can also match numbers in other writing systems like Chinese, Arabic, or Roman numerals.

Using p{N} in Regular Expressions

Now that we know what p{N} is, let’s see how we can use it in our regular expressions. To match any number in a string, we can simply include p{N} in our regex pattern. For example, to find all the numbers in a string, we can use the following code:

const myString = "The number is 42";
const regex = /\p{N}/ug;

console.log(myString.match(regex)); // Output: ["4", "2"]

Let’s break down this code. First, we create a variable myString that contains our string. We then create a regular expression regex that includes p{N}. We also use the u and g flags to indicate that our regex pattern uses Unicode characters and should find all the matches.

Finally, we use the match() method to find all the matches in our string. This method returns an array of all the matches.

Matching Different Types of Numbers

p{N} is not restricted to just the Arabic numerals. It can also match other types of numbers. For example, let’s say we wanted to match all the Chinese numbers in a string. We can use p{Number} to match any Chinese number like so:

const myString = "我有三百块钱";
const regex = /\p{Number}/ug;

console.log(myString.match(regex)); // Output: ["三", "百"]

In this code, we created a variable myString that contains a Chinese string. We then created a regular expression regex that includes p{Number}. We again used the u and g flags to indicate that our regex pattern uses Unicode characters and should find all the matches.

Finally, we use the match() method to find all the matches in our string. This returns an array of all the Chinese numbers in our string.

Conclusion

Regular expressions are an incredibly powerful tool for working with strings in JavaScript. The p{N} property is a Unicode property that matches any number in a string. It’s not restricted to just Arabic numerals but can match numbers in other writing systems like Chinese or Roman. Hopefully, this article has given you a better understanding of how to use p{N} in your JavaScript regular expressions.