| 'use strict'; | 
| // TODO: Remove from `core-js@4` | 
| var DESCRIPTORS = require('../internals/descriptors'); | 
| var addToUnscopables = require('../internals/add-to-unscopables'); | 
| var toObject = require('../internals/to-object'); | 
| var lengthOfArrayLike = require('../internals/length-of-array-like'); | 
| var defineBuiltInAccessor = require('../internals/define-built-in-accessor'); | 
|   | 
| // `Array.prototype.lastIndex` getter | 
| // https://github.com/keithamus/proposal-array-last | 
| if (DESCRIPTORS) { | 
|   defineBuiltInAccessor(Array.prototype, 'lastIndex', { | 
|     configurable: true, | 
|     get: function lastIndex() { | 
|       var O = toObject(this); | 
|       var len = lengthOfArrayLike(O); | 
|       return len === 0 ? 0 : len - 1; | 
|     } | 
|   }); | 
|   | 
|   addToUnscopables('lastIndex'); | 
| } |