You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
 
 
 
 
 
huazhiyu/node_modules/core-js/modules/es.function.has-instance.js

23 lines
1.0 KiB

'use strict';
var isCallable = require('../internals/is-callable');
var isObject = require('../internals/is-object');
var definePropertyModule = require('../internals/object-define-property');
var getPrototypeOf = require('../internals/object-get-prototype-of');
var wellKnownSymbol = require('../internals/well-known-symbol');
var makeBuiltIn = require('../internals/make-built-in');
var HAS_INSTANCE = wellKnownSymbol('hasInstance');
var FunctionPrototype = Function.prototype;
// `Function.prototype[@@hasInstance]` method
// https://tc39.es/ecma262/#sec-function.prototype-@@hasinstance
if (!(HAS_INSTANCE in FunctionPrototype)) {
definePropertyModule.f(FunctionPrototype, HAS_INSTANCE, { value: makeBuiltIn(function (O) {
if (!isCallable(this) || !isObject(O)) return false;
var P = this.prototype;
if (!isObject(P)) return O instanceof this;
// for environment w/o native `@@hasInstance` logic enough `instanceof`, but add this:
while (O = getPrototypeOf(O)) if (P === O) return true;
return false;
}, HAS_INSTANCE) });
}