This is an experimental technology
Because this technology's specification has not stabilized, check the compatibility table for usage in various browsers. Also note that the syntax and behavior of an experimental technology is subject to change in future versions of browsers as the specification changes.
WebAssembly.Instance object is a stateful, executable instance of a WebAssembly.Module.
WebAssembly.Instance() constructor function can be called to synchronously instantiate a given
WebAssembly.Module object. However, the primary way to get an
Instance is through the asynchronous
Important: Since instantiation for large modules can be expensive, developers should only use the
Instance() constructor when synchronous instantiation is absolutely required; the asynchronous
WebAssembly.instantiate() method should be used at all other times.
var myInstance = new WebAssembly.Instance(module, importObject);
WebAssembly.Moduleobject to be instantiated.
- importObject Optional
- An object containing the values to be imported into the newly-created
Instance, such as functions or
WebAssembly.Memoryobjects. There must be one matching property for each declared import of
moduleor else a WebAssembly.LinkError is thrown.
Instance instances inherit from the
Instance() constructor's prototype object — this can be modified to affect all
- Returns the function that created this object's instance. By default this is the
The definition of 'Instance' in that specification.
|Draft||Initial draft definition.|
|Feature||Chrome||Edge||Firefox (Gecko)||Internet Explorer||Opera||Safari (WebKit)|
|Basic support||57||No support||52 (52)||No support||(Yes)||No support|
|Feature||Chrome for Android||Android Webview||Edge Mobile||Firefox Mobile (Gecko)||IE Mobile||Opera Mobile||Safari Mobile|
|Basic support||57||57||No support||52.0 (52)||No support||No support||No support|
 WebAssembly is enabled in Firefox 52+, although disabled in the Firefox 52 Extended Support Release (ESR.)