Is there a reason to use an iterator rather than an array?

[Arlen22]

class TryResult extends Array {
  constructor(ok, val){
    super(3);

    if(!ok) { this.ok = false; this.error = val; }
    else { this.ok = true; this.value = val; }

    this[0] = this.ok
    this[1] = this.error;
    this[2] = this.value;

  }
}

[arthurfiorette]

I don't like the idea of both result instanceof Array and Array.isArray(result) be true. Not even talking about result.push() or result.flatMap().

There's no sense of it being an array ihmo

[ljharb]

It can certainly be arraylike, but definitely shouldn't be an array - not only would that incur a large performance hit with all of the array methods, most of which wouldn't make sense on a Result anyways.

Also, destructuring syntax always uses an iterator, including on arrays.

[DScheglov]

Actually extending array we do this exactly to get the [Symbol.iterator]-method. So, if we can just implement method why do we need the "Jungles"?