new Iterator() should throw TypeError?

[sosukesuzuki]

The following assertion is included in the file /test/built-ins/Iterator/newtarget-or-active-function-object.js:

assert.throws(TypeError, () => {
  new Iterator();
});

Is this correct?

According to section 3.1.1.1 of the proposed specification ¹,

it is designed to be subclassable. It may be used as the value of an extends clause of a class definition.

However, section 3.1.1.1.1 ² states:

2. Return ? OrdinaryCreateFromConstructor(NewTarget, "%Iterator.prototype%").

This does not mention throwing a TypeError.

Should a call to new Iterator() throw a TypeError, or should it return a value that inherits from Iterator.prototype?

Footnotes

1. https://tc39.es/proposal-iterator-helpers/#sec-iterator-constructor ↩

2. https://tc39.es/proposal-iterator-helpers/#sec-iterator ↩

[nicolo-ribaudo]

When you do new Iterator, NewTarget and "the active function object" are equal (both Iterator) and so step 1 of 3.1.1.1.1 throws.

[sosukesuzuki]

Ahh I got it.., thanks