WebAssembly.module.exports

The exports() method of the WebAssembly.Module() constructor returns an array containing references to the exported functions available in a given WebAssembly module.

Syntax

var custSec = WebAssembly.Module.exports(module);

Parameters

module

A WebAssembly.Module object instance.

Return value

An array containing objects representing the exported functions of the given module.

Exceptions

If module is not a WebAssembly.Module object instance, a TypeError is thrown.

Example

The following example compiles and instantiates the loaded simple.wasm byte code, importing a JavaScript function into the WebAssembly Module in the process. It then exports a function from the module via Instance.exports.

In addition, we create two variables, storing in them the exports and imports properties of the module instance mod.

var importObject = {
  imports: {
    imported_func: function(arg) {
      console.log(arg);
    }
  }
};

fetch('simple.wasm').then(function(response) {
  response.arrayBuffer().then(function(bytes) {
    WebAssembly.compile(bytes).then(function(mod) {
      var instance = new WebAssembly.Instance(mod, importObject);
      instance.exports.exported_func();

      var exports = WebAssembly.Module.exports(mod);
      var imp = WebAssembly.Module.imports(mod);
      console.log(exports[0]);
      console.log(imp[0]);
    })
  })
});

In this case, console.log(exports[0]) returns an object containing information about the exported function exported_func(). It looks like this:

{ name: "exported_func", kind: "function" }

Specifications

Specification	Status	Comment
Web Assembly JavaScript API The definition of 'exports()' in that specification.	Draft	Initial draft definition.

Browser compatibility

[1] Experimental support can be enabled in Chrome 51+ and Opera 38+ by going to chrome://flags and enabling the Experimental WebAssembly flag.

[2] Experimental support can be enabled in Firefox 47+ by enabling the javascript.options.wasm flag in about:config.

See also

• WebAssembly landing page.
• WebAssembly concepts
• Using the WebAssembly JavaScript API