André Bargull (2013-09-24T19:15:19.000Z)
domenic at domenicdenicola.com (2013-10-01T20:34:19.821Z)
> I look at the the opposite way -- we have an 'hasOwn' trap because be have a [[HasOwnProperty]] internal method ;-) > > I pretty sure we discussed this before and decided we wanted to keep [[HasOwnProperty]]. However, the only reason I can think of for doing so now is to avoid forcing exotic objects to allocated the property descriptors that [[GetOwnProperty]] produces. Exotic string and integer indexed objects ( = TypedArray instances) provide custom implementations for [[HasOwnProperty]] for exactly this reason. > Right, an none of the places seem particularly performance sensitive. In particular, ordinary property lookup uses [[GetOwnProperty]] rather than [[HasOwnProperlty]] [[HasProperty]] for ordinary objects also uses [[HasOwnProperty]]. So this needs to be taken into account when searching for performance sensitive calls.