2 var $ = require('../internals/export');
3 var flattenIntoArray = require('../internals/flatten-into-array');
4 var aCallable = require('../internals/a-callable');
5 var toObject = require('../internals/to-object');
6 var lengthOfArrayLike = require('../internals/length-of-array-like');
7 var arraySpeciesCreate = require('../internals/array-species-create');
9 // `Array.prototype.flatMap` method
10 // https://tc39.es/ecma262/#sec-array.prototype.flatmap
11 $({ target: 'Array', proto: true }, {
12 flatMap: function flatMap(callbackfn /* , thisArg */) {
13 var O = toObject(this);
14 var sourceLen = lengthOfArrayLike(O);
16 aCallable(callbackfn);
17 A = arraySpeciesCreate(O, 0);
18 A.length = flattenIntoArray(A, O, O, sourceLen, 0, 1, callbackfn, arguments.length > 1 ? arguments[1] : undefined);