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- var binaryIndex = require('../internal/binaryIndex'),
- indexOfNaN = require('../internal/indexOfNaN');
- /* Native method references for those with the same name as other `lodash` methods. */
- var nativeMax = Math.max,
- nativeMin = Math.min;
- /**
- * This method is like `_.indexOf` except that it iterates over elements of
- * `array` from right to left.
- *
- * @static
- * @memberOf _
- * @category Array
- * @param {Array} array The array to search.
- * @param {*} value The value to search for.
- * @param {boolean|number} [fromIndex=array.length-1] The index to search from
- * or `true` to perform a binary search on a sorted array.
- * @returns {number} Returns the index of the matched value, else `-1`.
- * @example
- *
- * _.lastIndexOf([1, 2, 1, 2], 2);
- * // => 3
- *
- * // using `fromIndex`
- * _.lastIndexOf([1, 2, 1, 2], 2, 2);
- * // => 1
- *
- * // performing a binary search
- * _.lastIndexOf([1, 1, 2, 2], 2, true);
- * // => 3
- */
- function lastIndexOf(array, value, fromIndex) {
- var length = array ? array.length : 0;
- if (!length) {
- return -1;
- }
- var index = length;
- if (typeof fromIndex == 'number') {
- index = (fromIndex < 0 ? nativeMax(length + fromIndex, 0) : nativeMin(fromIndex || 0, length - 1)) + 1;
- } else if (fromIndex) {
- index = binaryIndex(array, value, true) - 1;
- var other = array[index];
- if (value === value ? (value === other) : (other !== other)) {
- return index;
- }
- return -1;
- }
- if (value !== value) {
- return indexOfNaN(array, index, true);
- }
- while (index--) {
- if (array[index] === value) {
- return index;
- }
- }
- return -1;
- }
- module.exports = lastIndexOf;
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