TypeScript Plugin BigInt

A TypeScript transformer that converts BigInt operators to library calls.

Features

• Replaces all addition operators (+) with add function calls
• Automatically imports the add function from the bigint-runtime library
• Avoids duplicate imports, only adding import statements when needed
• Supports correct conversion of nested expressions
• Easily integrates into existing TypeScript projects
• Provides complete type definitions

Installation

# Install the plugin
pnpm i -D typescript-plugin-bigint

# Install runtime dependency
pnpm i bigint-runtime

Usage

With Rollup

// rollup.config.js
const typescript = require('@rollup/plugin-typescript');
const bigIntPlugin = require('typescript-plugin-bigint').default;

module.exports = {
	// ...other options
	plugins: [
		typescript({
			transformers: (program) => ({
				before: [
					bigIntPlugin(program)
				]
			})
		})
	]
};

With webpack's ts-loader

In your webpack configuration:

const bigIntPlugin = require('typescript-plugin-bigint').default;

module.exports = {
	// ...other configuration
	module: {
		rules: [
			{
				test: /\.tsx?$/,
				loader: 'ts-loader',
				options: {
					getCustomTransformers: (program) => ({
						before: [
							bigIntPlugin(program)
						]
					})
				}
			}
		]
	}
};

With ts-patch/ttypescript

{
	"compilerOptions": {
		"plugins": [
			{ "transform": "typescript-plugin-bigint" }
		]
	}
}

Transformation Examples

Before

export function add(a: bigint, b: bigint) {
	return a + b;
}

After

import * as JSBI from "bigint-runtime";
export function add(a: bigint, b: bigint) {
	return JSBI.add(a, b);
}

Supported Operations

The plugin transforms various BigInt operations to their corresponding library calls:

Literal Transformations

| Operation | Before | After | | -------------------- | ----------------------- | --------------------------------- | | literals | a = 123n; | JSBI.BigInt(123) | | literals | a = 9007199254740993n | JSBI.BigInt('9007199254740993') | | Creation from String | a = BigInt('456') | a = JSBI.BigInt('456') | | Creation from Number | a = BigInt(789) | a = JSBI.BigInt(789) | | Conversion to String | a.toString(radix) | a.toString(radix) | | Conversion to Number | Number(a) | JSBI.toNumber(a) | | Truncation | BigInt.asIntN(64, a) | JSBI.asIntN(64, a) | | | BigInt.asUintN(64, a) | JSBI.asUintN(64, a) |

BigInt Operations

| Operation | Before | After | | --------------------------- | ------------ | --------------------------------- | | Addition | c = a + b | c = JSBI.add(a, b) | | Subtraction | c = a - b | c = JSBI.subtract(a, b) | | Multiplication | c = a * b | c = JSBI.multiply(a, b) | | Division | c = a / b | c = JSBI.divide(a, b) | | Remainder | c = a % b | c = JSBI.remainder(a, b) | | Exponentiation | c = a ** b | c = JSBI.exponentiate(a, b) | | Negation | b = -a | b = JSBI.unaryMinus(a) | | Bitwise negation | b = ~a | b = JSBI.bitwiseNot(a) | | Left shifting | c = a << b | c = JSBI.leftShift(a, b) | | Right shifting | c = a >> b | c = JSBI.signedRightShift(a, b) | | Bitwise "and" | c = a & b | c = JSBI.bitwiseAnd(a, b) | | Bitwise "or" | c = a \| b | c = JSBI.bitwiseOr(a, b) | | Bitwise "xor" | c = a ^ b | c = JSBI.bitwiseXor(a, b) | | Comparison to other BigInts | a === b | JSBI.equal(a, b) | | | a !== b | JSBI.notEqual(a, b) | | | a < b | JSBI.lessThan(a, b) | | | a <= b | JSBI.lessThanOrEqual(a, b) | | | a > b | JSBI.greaterThan(a, b) | | | a >= b | JSBI.greaterThanOrEqual(a, b) |

Mixed-type Operations

| Operation | Before | After | | ------------------------------- | -------- | ---------------- | | Abstract equality comparison | x == y | JSBI.EQ(x, y) | | Generic "not equal" | x != y | JSBI.NE(x, y) | | Generic "less than" | x < y | JSBI.LT(x, y) | | Generic "less than or equal" | x <= y | JSBI.LE(x, y) | | Generic "greater than" | x > y | JSBI.GT(x, y) | | Generic "greater than or equal" | x >= y | JSBI.GE(x, y) | | Generic addition | x + y | JSBI.ADD(x, y) |

Partially Supported Operations

Some operations have limited support:

| Operation | Before | After | | ----------- | ----------------------- | ------------------ | | Type check | typeof a === "bigint" | JSBI.isBigInt(a) | | Type check | typeof a | JSBI.isObject(a) | | Type check | typeof a | JSBI.typeOf(a) | | increment | a++ | N/A ☹ | | decrement | a-- | N/A ☹ | | increment | ++a | N/A ☹ | | decrement | --a | N/A ☹ | | assignment | a += 1n | N/A ☹ | | assignment | a -= 1n | N/A ☹ | | assignment | a *= 1n | N/A ☹ | | assignment | a /= 1n | N/A ☹ | | 0n is falsy | 0n ? 1 : 0 | N/A ☹ |