| 'use strict'; |
| var isObject = require('./_is-object') |
| , getPrototypeOf = require('./_object-gpo') |
| , HAS_INSTANCE = require('./_wks')('hasInstance') |
| , FunctionProto = Function.prototype; |
| // 19.2.3.6 Function.prototype[@@hasInstance](V) |
| if(!(HAS_INSTANCE in FunctionProto))require('./_object-dp').f(FunctionProto, HAS_INSTANCE, {value: function(O){ |
| if(typeof this != 'function' || !isObject(O))return false; |
| if(!isObject(this.prototype))return O instanceof this; |
| // for environment w/o native `@@hasInstance` logic enough `instanceof`, but add this: |
| while(O = getPrototypeOf(O))if(this.prototype === O)return true; |
| return false; |
| }}); |