The self read-only property of the WorkerGlobalScope interface returns a reference to the WorkerGlobalScope itself. Most of the time it is a specific scope like DedicatedWorkerGlobalScopeSharedWorkerGlobalScope, or ServiceWorkerGlobalScope.

Syntax

var selfRef = self;

Value

A global scope object (differs depending on the type of worker you are dealing with, as indicated above).

Example

If you called

console.log(self);

inside a worker, you will get a worker global scope of the same type as that worker object written to the console — something like the following:

DedicatedWorkerGlobalScope {
undefined: undefined, Infinity: Infinity, Math: MathConstructor, NaN: NaN, Intl: Object…}
    Infinity: Infinity
    Array: function Array() { [native code] }
      arguments: null
      caller: null
      isArray: function isArray() { [native code] }
      length: 1
      name: "Array"
      observe: function observe() { [native code] }
      prototype: Array[0]
      unobserve: function unobserve() { [native code] }
      __proto__: function Empty() {}
      <function scope>
    ArrayBuffer: function ArrayBuffer() { [native code] }
    Blob: function Blob() { [native code] }
    Boolean: function Boolean() { [native code] }
    DataView: function DataView() { [native code] }
    Date: function Date() { [native code] }
    DedicatedWorkerGlobalScope: function DedicatedWorkerGlobalScope() { [native code] }
    Error: function Error() { [native code] }
// etc. etc.

This provides a full list of the objects available to that worker scope, so it is quite a useful test if you want to see whether something is available to your worker or not. We also maintain a list of Functions and classes available to Web Workers.

Specifications

Specification Status Comment
HTML Living Standard
The definition of 'self' in that specification.
Living Standard  

Browser compatibility

 

Update compatibility data on GitHub
DesktopMobile
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidEdge MobileFirefox for AndroidOpera for AndroidSafari on iOSSamsung Internet
Basic supportChrome Full support 4Edge ? Firefox Full support 3.5IE Full support YesOpera Full support 11.5Safari Full support 4WebView Android ? Chrome Android Full support 40Edge Mobile ? Firefox Android Full support 34Opera Android Full support YesSafari iOS Full support 5.1Samsung Internet Android Full support 4.0

Legend

Full support  
Full support
Compatibility unknown  
Compatibility unknown

 

See also

WorkerGlobalScope

Document Tags and Contributors

Last updated by: philippotto,