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Map() - JavaScript | MDN
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Map()

Baseline

20157

Map() Map

js
new Map()
new Map(iterable)

: Map() new new TypeError

iterable

Map 0 1 2 [[1, "one"],[2, "two"]] null undefined Map

Map

js
const myMap = new Map([
  [1, "one"],
  [2, "two"],
  [3, "three"],
]);

ECMAScript 2027 LanguageSpecification
# sec-map-constructor

MDN

MDN 2026521

GitHub
  2. Map
    1. Map()
    1. groupBy()
    1. [Symbol.species]
    1. clear()
    2. delete()
    3. entries()
    4. forEach()
    5. get()
    6. getOrInsert()
    7. getOrInsertComputed()
    8. has()
    9. keys()
    10. set()
    11. values()
    12. [Symbol.iterator]()
    1. size
  9. Object/Function
    1. apply()
    2. bind()
    3. call()
    4. toString()
    5. [Symbol.hasInstance]()
    1. displayName
    2. length
    3. name
    4. prototype
    5. arguments
    6. caller
    1. __defineGetter__()
    2. __defineSetter__()
    3. __lookupGetter__()
    4. __lookupSetter__()
    5. hasOwnProperty()
    6. isPrototypeOf()
    7. propertyIsEnumerable()
    8. toLocaleString()
    9. toString()
    10. valueOf()
    1. __proto__
    2. constructor
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