廃止 Gecko 2 (Firefox 4 / Thunderbird 3.3 / SeaMonkey 2.1)
This feature is obsolete. Although it may still work in some browsers, its use is discouraged since it could be removed at any time. Try to avoid using it.
__parent__ はオブジェクトのコンテクストへのポインタです。
obj.__parent____parent__ はオブジェクトのコンテクストへのポインタです。よって、例えば Web ブラウザでのトップレベルのオブジェクトの __parent__ の参照先は window オブジェクトとなります。
ObjectObject.assign() [Translate]Object.create()Object.defineProperties()Object.defineProperty()Object.freeze()Object.getOwnPropertyDescriptor()Object.getOwnPropertyNames()Object.getOwnPropertySymbols() [Translate]Object.getPrototypeOf()Object.is()Object.isExtensible()Object.isFrozen()Object.isSealed()Object.keys()Object.observe() [Translate]Object.preventExtensions()Object.prototype.__defineGetter__()Object.prototype.__defineSetter__()Object.prototype.__lookupGetter__()Object.prototype.__lookupSetter__()Object.prototype.eval()Object.prototype.hasOwnProperty()Object.prototype.isPrototypeOf()Object.prototype.propertyIsEnumerable()Object.prototype.toLocaleString()Object.prototype.toSource()Object.prototype.toString()Object.prototype.unwatch()Object.prototype.valueOf()Object.prototype.watch()Object.seal()Object.setPrototypeOf() [Translate]Function