ECMASCRIPT.md

ECMAScript and Node requirements

The goal of the document is to list features we rely on for the runtime and the generated code. Features are grouped by ECMAScript version.

ECMAScript 2015

Arrow function expressions

• Compatibility
• For Wasm_of_ocaml

Classes

• Compatibility

const

• Compatibility

for...of

• Compatibility

let

• Compatibility

Map

• Compatibility
• Used in runtime for data structures and object tracking

Object.assign

• Compatibility

Rest parameters

• Compatibility

Set

• Compatibility

Spread syntax (in function call)

• Compatibility

TypedArray

• Compatibility
• To implement bigarray

WeakMap

• Compatibility

ECMAScript 2016

async function

• Compatibility
• For Wasm_of_ocaml

await

• Compatibility
• For Wasm_of_ocaml

ECMAScript 2020

BigInt

• Compatibility
• For Wasm_of_ocaml

globalThis

• Compatibility
• Polyfilled in the repository

Optional chaining (?.)

• Compatibility

ECMAScript 2021

FinalizationRegistry

• Compatibility
• Optional for js_of_ocaml

WeakRef

• Compatibility
• To implement weak and ephemeron
• Optional

Web APIs

Canvas API

• Compatibility

Crypto API

• Compatibility

Document API

• Compatibility

Image API

• Compatibility

Performance API

• Compatibility

XMLHttpRequest

• Compatibility

Node.js

Built-in modules with node: prefix

• Compatibility

Child process

• Compatibility

File system

• Compatibility

Process

• Compatibility

TTY

• Compatibility

Util

• Compatibility