Editorial: Using non-negative integral Number instead of integral Number in ToLength

[tmdghks]

In current ECMA262 specification, the abstract operation ToLength returns a integer or throw completion.
However, I think that type of the return value of ToLength can be narrowed to a non-negative integer or throw completion.

[jmdyck]

In current ECMA262 specification, the abstract operation ToLength returns a integer or throw completion.

Not an integer, but an integral Number. That's an important distinction: in the ES spec's terminology, an integer is a "mathematical value", but a Number is a "language value". Those are completely disjoint value spaces, though they are related via conversion operations.

However, I think that type of the return value of ToLength can be narrowed to a non-negative integer or throw completion.

If you change "integer" back to "integral Number" there, I think that narrowing would be valid.

[tmdghks]

I'm sorry for incorrectly editing the specification.
I have corrected the term integer to integral Number in the specification of the ToLength abstract operation.
Thank you for your review.

[ljharb]

cc @jhnaldo for the esmeta failure; what do you recommend here? ignoring LengthOfArrayLike seems like an odd choice.

[michaelficarra]

@ljharb see the linked esmeta issue I created

[jhnaldo]

As I explained in es-meta/esmeta#260, the error message says that remove the line LengthOfArrayLike in the esmeta-ignore.json file because it no longer throws type errors caused by the imprecise return type of ToLength.

[ljharb]

Thanks, the “add/remove” confused me :-)