The well-known Symbol.toStringTag and its related changes in Object.prototype.toString --- is a stable API introduced in ECMA-262 6th edition draft from September 27, 2012, and has apparently not changed since its inception. The goal is to mitigate the use of Object.prototype.toString as a way of getting the [[Class]] value of an object [1, 2], and to provide a way to illustrate an object's type, which may be useful for dev tools.
I'd like to put this behind a flag --- not exposing Symbol.toStringTag until the semantics in O.p.toString are also available. There are a number of bugs fixed by this, including v8:3502 <https://code.google.com/p/v8/issues/detail?id=3502>, v8:3241 <https://code.google.com/p/v8/issues/detail?id=3241>, v8:3619 <https://code.google.com/p/v8/issues/detail?id=3619> *Design Doc / Patch* https://crrev.com/546803003/ *Other implementations* There are no other implementations currently. There is not currently a bug to implement on SpiderMonkey, nor JSC. *Technical considerations* None, It's a very simple feature. *Perf Considerations* It is likely that this will slow down Object.prototype.toString to some degree, but it's not clear how much of a hot spot O.p.toString really is in a typical application. [1] https://github.com/rwaldron/tc39-notes/blob/master/es6/2012-07/july-24.md [2] https://mail.mozilla.org/pipermail/es-discuss/2013-May/030699.html -- -- v8-users mailing list [email protected] http://groups.google.com/group/v8-users --- You received this message because you are subscribed to the Google Groups "v8-users" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
