On 21 August 2013 15:41, Erik Arvidsson <erik.arvids...@gmail.com> wrote: > One way to think of it is that the with is acting on a view of the > object that does not have the blacklisted properties. This can be > implemented using proxies. I'll leave that as an exercise.
I see. >> * How would it interact with mutation? > > Another hole we didn't cover. Here is my proposal: > > The @@unscopable is only accessed once, when the object environment > record is created. Hm, that would seem rather inconsistent with the way adding/removing properties can dynamically change the domain of a 'with'. Consider: function safeenrich(o) { o.a = 1 o[@@unscopable] = o[@@unscopable] || [] o[@@unscopable].push('a') } let o = {} let a = 0 with (o) { a // 0 safeenrich(o) a // 1 } /Andreas _______________________________________________ es-discuss mailing list es-discuss@mozilla.org https://mail.mozilla.org/listinfo/es-discuss