WebAssembly.Instance.prototype.exports
  The exports readonly property of the
  WebAssembly.Instance object prototype returns an object containing as its
  members all the functions exported from the WebAssembly module instance, to allow them
  to be accessed and used by JavaScript.
Examples
Using exports
  After fetching some WebAssembly bytecode using fetch, we compile and instantiate the
  module using the WebAssembly.instantiateStreaming() function, importing a
  JavaScript function into the WebAssembly Module in the process. We then call an Exported WebAssembly function
  that is exported by the Instance.
js
const importObject = {
  imports: {
    imported_func(arg) {
      console.log(arg);
    },
  },
};
WebAssembly.instantiateStreaming(fetch("simple.wasm"), importObject).then(
  (obj) => obj.instance.exports.exported_func()
);
Note: You can also find this example as instantiate-streaming.html on GitHub (view it live also).
Specifications
| Specification | 
|---|
| WebAssembly JavaScript Interface # dom-instance-exports | 
Browser compatibility
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