| 12345678910111213141516171819202122232425262728293031323334 | 'use strict';var isArray = require('../internals/is-array');var lengthOfArrayLike = require('../internals/length-of-array-like');var doesNotExceedSafeInteger = require('../internals/does-not-exceed-safe-integer');var bind = require('../internals/function-bind-context');// `FlattenIntoArray` abstract operation// https://tc39.github.io/proposal-flatMap/#sec-FlattenIntoArrayvar flattenIntoArray = function (target, original, source, sourceLen, start, depth, mapper, thisArg) {  var targetIndex = start;  var sourceIndex = 0;  var mapFn = mapper ? bind(mapper, thisArg) : false;  var element, elementLen;  while (sourceIndex < sourceLen) {    if (sourceIndex in source) {      element = mapFn ? mapFn(source[sourceIndex], sourceIndex, original) : source[sourceIndex];      if (depth > 0 && isArray(element)) {        elementLen = lengthOfArrayLike(element);        targetIndex = flattenIntoArray(target, original, element, elementLen, targetIndex, depth - 1) - 1;      } else {        doesNotExceedSafeInteger(targetIndex + 1);        target[targetIndex] = element;      }      targetIndex++;    }    sourceIndex++;  }  return targetIndex;};module.exports = flattenIntoArray;
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