7 ms·
As I understand it, the main objection to `__proto__` is that it's writable, and thus not atomic with object creation. This creates a bunch of headaches for imp
by alunny 15y ago
As I understand it, the main objection to `__proto__` is that it's writable, and thus not atomic with object creation. This creates a bunch of headaches for implementors for performance and security.
More knowledgable people than myself discuss it on this es-discuss thread:
http://www.mail-archive.com/es-discuss@mozilla.org/msg06142.html http://www.mail-archive.com/es-discuss@mozilla.org/msg06142....
There is a Harmony proposal for a "set prototype of operator" that would solve this problem; instead of writing:
var newObj = {__proto__: OldObject, id: 5}
You would write:
var newObj = OldObject <| { id: 5 }
Detailed here:
http://wiki.ecmascript.org/doku.php?id=harmony:proto_operator http://wiki.ecmascript.org/doku.php?id=harmony:proto_operato...
- Cushman 15y agoYeah, I can understand how it makes implementors' lives easier... I just like it when they deal with annoying stuff so that I don't have to :) I know people don't use mutable __proto__ for anything useful, but it does enable some neat tricks. Personally I wish implementors would embrace it and optimize for it rather than trying to make it go away. As for the "prototype for" operator... that's disgusting.