[[DefineOwnProperty]] wording nit

Allen Wirfs-Brock Allen.Wirfs-Brock at microsoft.com
Thu Sep 17 18:12:13 PDT 2009


>-----Original Message-----
>From: es-discuss-bounces at mozilla.org [mailto:es-discuss-
>bounces at mozilla.org] On Behalf Of Jeff Walden
>...
>
>> Perhaps modifying step 7b to explicitly say "Reject, if [[Enumerable]]
>> is present in Desc and...", is a less arcane approach to fixing this.
>> (That might not be the only change needed though.)
>
>This isn't what I'd thought we meant, but it seems to be the newly-
>adopted change in errata, and indeed I prefer it to the one I thought we
>meant -- much more intuitive.

Yes, that was always the intent. Think about it from the perspective of Object.defineProperty.  If you are defining a new property a missing attribute is supposed to mean use its default value.  If you are redefining an existing property a missing attribute is supposed to mean keep the existing value.  Most of the logic in [[DefineOwnProperty]] is rejecting invalid or inconsistent redefinitions.

Allen


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