1234567891011121314151617181920212223 |
- 'use strict';
- var $export = require('./_export');
- var toIObject = require('./_to-iobject');
- var toInteger = require('./_to-integer');
- var toLength = require('./_to-length');
- var $native = [].lastIndexOf;
- var NEGATIVE_ZERO = !!$native && 1 / [1].lastIndexOf(1, -0) < 0;
- $export($export.P + $export.F * (NEGATIVE_ZERO || !require('./_strict-method')($native)), 'Array', {
- // 22.1.3.14 / 15.4.4.15 Array.prototype.lastIndexOf(searchElement [, fromIndex])
- lastIndexOf: function lastIndexOf(searchElement /* , fromIndex = @[*-1] */) {
- // convert -0 to +0
- if (NEGATIVE_ZERO) return $native.apply(this, arguments) || 0;
- var O = toIObject(this);
- var length = toLength(O.length);
- var index = length - 1;
- if (arguments.length > 1) index = Math.min(index, toInteger(arguments[1]));
- if (index < 0) index = length + index;
- for (;index >= 0; index--) if (index in O) if (O[index] === searchElement) return index || 0;
- return -1;
- }
- });
|