1. ECMAScript 5

    Full support for the ECMAScript 5 specification. Features include `Function.prototype.bind`, Array methods like `indexOf`, `forEach`, `map` & `filter`, Object methods like `defineProperty`, `create` & `keys`, the `trim` method on Strings and many more.

  2. ECMAScript 2015 (ES6)

    Support for the ECMAScript 2015 specification. Features include Promises, Modules, Classes, Template Literals, Arrow Functions, Let and Const, Default Parameters, Generators, Destructuring Assignment, Rest & Spread, Map/Set & WeakMap/WeakSet and many more.

  3. Import maps

    Import maps allows control over what URLs get fetched by JavaScript `import` statements and `import()` expressions.

  4. javascript built-in: array: flatmap

  5. javascript built-in: array: map

  6. javascript built-in: asynciterator: flatmap

  7. javascript built-in: asynciterator: map

  8. javascript built-in: iterator: flatmap

  9. javascript built-in: iterator: map

  10. javascript built-in: map

  11. javascript built-in: map: @@iterator

  12. javascript built-in: map: @@species

  13. javascript built-in: map: @@tostringtag

  14. javascript built-in: map: clear

  15. javascript built-in: map: delete

  16. javascript built-in: map: entries

  17. javascript built-in: map: foreach

  18. javascript built-in: map: get

  19. javascript built-in: map: has

  20. javascript built-in: map: keys

  21. javascript built-in: map: key equality for -0 and 0

  22. javascript built-in: map: `map()` constructor

  23. javascript built-in: map: `map()` constructor: `new map(iterable)`

  24. javascript built-in: map: `map()` constructor: `map()` without `new` throws

  25. javascript built-in: map: `map()` constructor: `new map(null)`

  26. javascript built-in: map: set

  27. javascript built-in: map: size

  28. javascript built-in: map: values

  29. javascript built-in: typedarray: map

  30. javascript built-in: weakmap

  31. javascript built-in: weakmap: clear

  32. javascript built-in: weakmap: delete

  33. javascript built-in: weakmap: get

  34. javascript built-in: weakmap: has

  35. javascript built-in: weakmap: set

  36. javascript built-in: weakmap: `weakmap()` constructor

  37. javascript built-in: weakmap: `weakmap()` constructor: `new weakmap(iterable)`

  38. javascript built-in: weakmap: `weakmap()` constructor: `weakmap()` without `new` throws

  39. javascript built-in: weakmap: `weakmap()` constructor: `new weakmap(null)`

  40. javascript function: arguments: @@iterator