Should an @@unscopables property also be defined for globals?

[tobie]

No description provided.

[ExE-Boss]

What would this do?

Can you provide reasoning as to why we might want to do or not do this?

[annevk]

It was a question in #494. I don't think there's a need for this and in general we haven't really used unscopables much.

[bathos]

The spec still links to this issue in a note at step 10 of “create an interface prototype object”:

Should an @@unscopables property also be defined if interface is declared with the [Global] extended attribute? This is discussed in issue #544.

The “also be” in the note is maybe misleading because the steps which follow it do define @@unscopables properties on interface prototype objects for [Global] interfaces if they have [Unscopable] members. AFAICT there just aren’t any qualifying interfaces being defined out there in practice.

Maybe the note should be removed now? It seems pretty harmless that it’s presently permitted, but if it were desirable to expressly forbid it, the place to do that wouldn’t be in those steps anyway — it’d be in the definition of [Unscopable] (e.g. “[Unscopable] must not be declared on members of [Global] interfaces” etc).