Re: [heycam/webidl] Help specifying WebAssembly.Function (#937)

> Could you help write some JS code that reifies `WebAssembly.Function`?

My understanding is that `WebAssembly.Function` instances are supposed to have a `[[Call]]` internal method (i.e.: their `typeof` is `"function"`), the following TypeScript‑like pseudocode demonstrates a way that could be accomplished:

```ts
interface WebAssembly.Function {
 // Instances of `WasmFunction` are callable
 (...args: any): any;
}
class WebAssembly.Function extends globalThis.Function {
 /**
  * The `[[FunctionAddress]]` internal slot.
  *
  * @see https://webassembly.github.io/spec/js-api/#exported-function-exotic-objects

  */
 #FunctionAddress: number;

 constructor(type: FunctionType, func: globalThis.Function) {
  const parameters = Array.from(type.parameters, ToString);
  const results = Array.from(type.results, ToString);

  const F: WebAssembly.Function = Object.setPrototypeOf(
   /** @see https://webassembly.github.io/spec/js-api/#call-an-exported-function */
   (...args: unknown[]) => call_exported_function(F.#FunctionAddress, args),
   new.target.prototype,
  );

  /** @see https://github.com/littledan/proposal-new-initialize */
  new.initialize(F);

  /** @see https://webassembly.github.io/spec/js-api/#create-a-host-function */
  F.#FunctionAddress = create_host_function(func, {
   paramTypes: parameters,
   resultTypes: results,
  });

  return F;
 }

 type(): FunctionType {
  /** @see https://webassembly.github.io/spec/js-api/#associated-store */
  const store = surroundingAgent.wasmStore;

  /** @see https://webassembly.github.io/spec/core/appendix/embedding.html#embed-func-type */
  const functype = func_type(store, this.#FunctionAddress);

  return {
   parameters: Array.from(functype.paramTypes),
   results: Array.from(functype.resultTypes),
  };
 }
}
```

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