JS: Map.prototype.entries

By Xah Lee. Date: . Last updated: .

(new in ECMAScript 2015)

mapObj.entries()
  • Return a Generator for the map.
  • Each yield is a array of the form [key, value].
const mm = new Map([[3, "aa"], [4, "bb"]]);
for (let [k, v] of mm.entries()) {
 console.log(k, v);
}
// 3 aa
// 4 bb

Map.prototype.entries is the same as Map.prototype[Symbol.iterator]

console.assert(
 Map.prototype.entries ===
  Map.prototype[Symbol.iterator],
);