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A comment on Understanding "Prototypes" in JavaScript. Parent comment

Re:Understanding "Prototypes" in JavaScript by alunny on Sunday August 14, 2011 @02:40PM (#2884148)
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/[email protected]/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_operato...
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Re:Understanding "Prototypes" in JavaScript by Cushman on Sunday August 14, 2011 @09:21PM (#2885040)
Yeah, 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.

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