"not a Date object" vs. "not an object with [[Class]] of ''Date''"

Brendan Eich brendan at mozilla.com
Sat Oct 2 06:29:38 PDT 2010


On Sep 6, 2010, at 1:43 AM, Dmitry A. Soshnikov wrote:

> For what to create a proxy? It's only for catch-traps (yes, it may be used additionally to create a _catcher_ with "Array" [[Class]], but without additions -- i.e. if a user wants just to inherit from Array.prototype and to have all arrays' stuff -- proxies are not needed to him).

Proxies are required to update length to be one greater than index (property name-string P such that ToString(ToUint32(P)) == P and ToUint32(P) is not 2^32 - 1) when setting an indexed property. Array's magic [[Put]] is not inherited.

/be



More information about the es-discuss mailing list