JavaScript BigInt

Introduction

BigInt is a primitive type in JavaScript that allows you to represent whole numbers larger than 253 – 1. This is because JavaScript numbers are stored in a 64-bit floating-point format, which limits the largest integer that can be represented to 9,007,199,254,740,991.

Creating BigInts

There are two ways to create BigInts:

Using the BigInt literal syntax: You can create a BigInt literal by appending the letter n to the end of an integer literal. For example:

const bigInt1 = 12345678901234567890n;

Using the BigInt() function: You can also create a BigInt using the BigInt() function. The BigInt() function takes an integer literal or string as its argument and returns a BigInt value. For example:

const bigInt2 = BigInt(12345678901234567890);

Using BigInts

Once you have created a BigInt, you can use it like any other JavaScript number. You can perform arithmetic operations on BigInts, compare them, and convert them to other types.

Here are some examples of using BigInts:

// Add two BigInts
const bigIntSum = bigInt1 + bigInt2;
// Subtract two BigInts
const bigIntDifference = bigInt1 - bigInt2;
// Multiply two BigInts
const bigIntProduct = bigInt1 * bigInt2;
// Divide two BigInts
const bigIntQuotient = bigInt1 / bigInt2;
// Compare two BigInts
const isBigInt1GreaterThanBigInt2 = bigInt1 > bigInt2;
// Convert a BigInt to a string
const bigIntAsString = bigInt1.toString();

BigInt Coercion

Many built-in JavaScript operations that expect numbers will automatically coerce BigInts to numbers. This means that you can use BigInts in most places where you would normally use numbers.

However, there are a few things to keep in mind when using BigInt coercion:

Coercing a BigInt to a number can lead to loss of precision, if the BigInt is too large to be represented as a number.

Some built-in operations, such as the Math.floor() and Math.ceil() functions, will truncate the BigInt to a fixed width after coercion.

It is generally recommended to only use BigInt coercion when it is necessary, and to avoid coercing BigInts to numbers if you are unsure whether the number will be too large to be represented accurately.

Use Cases for BigInts

BigInts can be used in a variety of applications, including:

Cryptography: BigInts are often used in cryptography to encrypt and decrypt data.

Financial applications: BigInts are used in financial applications to represent large monetary values.

Scientific computing: BigInts are used in scientific computing to perform calculations on large numbers.

Conclusion

BigInts are a powerful tool that can be used to represent and manipulate very large numbers. If you need to work with numbers that are too large to be represented as JavaScript numbers, then BigInts are the way to go.

Here are some additional tips for using BigInts:

Be aware of the precision limitations of BigInt coercion.

Avoid coercing BigInts to numbers if you are unsure whether the number will be too large to be represented accurately.

Use the BigInt() function to create BigInts from strings, as this is more efficient than parsing the string yourself.

Use the BigInt.asIntN() and BigInt.asUintN() methods to convert BigInts to fixed-width integers.

Be aware that some built-in operations, such as the Math.floor() and Math.ceil() functions, will truncate the BigInt to a fixed width after coercion.