The Proxy.revocable()
method is used to create a revocable Proxy
object.
Proxy.revocable(target, handler);
target
Proxy
.handler
A newly created revocable Proxy
object is returned.
A revocable Proxy
is an object with following two properties {proxy: proxy, revoke: revoke}
.
proxy
new Proxy(target, handler)
call.revoke
proxy
.If the revoke()
function gets called, the proxy becomes unusable: Any trap to a handler will throw a TypeError
. Once a proxy is revoked, it will remain revoked and can be garbage collected. Calling revoke()
again has no effect.
var revocable = Proxy.revocable({}, { get: function(target, name) { return "[[" + name + "]]"; } }); var proxy = revocable.proxy; console.log(proxy.foo); // "[[foo]]" revocable.revoke(); console.log(proxy.foo); // TypeError is thrown proxy.foo = 1 // TypeError again delete proxy.foo; // still TypeError typeof proxy // "object", typeof doesn't trigger any trap
Specification | Status | Comment |
---|---|---|
ECMAScript 2015 (6th Edition, ECMA-262) The definition of 'Proxy Revocation Functions' in that specification. | Standard | Initial definition. |
ECMAScript 2017 Draft (ECMA-262) The definition of 'Proxy Revocation Functions' in that specification. | Draft |
Feature | Chrome | Firefox (Gecko) | Internet Explorer | Opera | Safari |
---|---|---|---|---|---|
Basic support | (Yes) | 34 (34) | No support | No support | No support |
Feature | Android | Chrome for Android | Firefox Mobile (Gecko) | IE Mobile | Opera Mobile | Safari Mobile |
---|---|---|---|---|---|---|
Basic support | No support | No support | 34 (34) | No support | No support | No support |
© 2005–2017 Mozilla Developer Network and individual contributors.
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Proxy/revocable