The Complete Guide to ES10 Features

ES10 is no longer just a draft! All features have already been implemented in major browsers. Here is a non-alien guide for anyone interested in exploring ES10 (released June 2019.)

Ghost Together
12 min readFeb 20, 2019

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Complete CSS flex tutorial on Hashnode.

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Higher-order functions .map, .filter & .reduce on Hashnode.

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ES10 is not as significant as ES6 in terms of new features, but it does add several useful* things you might want to know about.

In ES6 arrow functions were hands down the most popular new feature.

What was it in ES10?

BigInt — Arbitrary precision integers

BigInt is the 7th primitive type.

BigInt is an arbitrary-precision integer. What this means is that variables can now represent 2⁵³ numbers. And not just max out at 9007199254740992.

const b = 1n; // append n to create a BigInt

In the past integer values greater than 9007199254740992 were not supported. If exceeded, the value would simply lock to MAX_SAFE_INTEGER + 1:

const limit = Number.MAX_SAFE_INTEGER;
9007199254740991
limit + 1;
9007199254740992
limit + 2;
9007199254740992 <--- MAX_SAFE_INTEGER + 1 exceeded
const larger = 9007199254740991n;
9007199254740991n
const integer = BigInt(9007199254740991); // initialize with number
9007199254740991n
const same = BigInt("9007199254740991"); // initialize with "string"
9007199254740991n

typeof

typeof 10;
'number'
typeof 10n;
'bigint'

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