My ECMAScript 7 wishlist

Tab Atkins Jr. jackalmage at
Wed Sep 24 15:17:32 PDT 2014

On Wed, Sep 24, 2014 at 2:56 PM, Brendan Eich <brendan at> wrote:
> Brendan Eich wrote:
>> Tab Atkins Jr. wrote:
>>> This works great as a general principle, but honestly tons of
>>> languages have already forged this path.  It's pretty straightforward,
>>> I think.
>> I made the case for building it in sooner, but TC39 wanted "less sooner"
>> based on library usage. There was a minority position (as voiced; could be
>> majority) that argued JS is different, object detection plus optional
>> "fields" means this is the wrong direction.
> Not trying to be controversial ;-). Would you use ES6 classes and have the
> ones you wrote all extend NoSuchPropertyClass?

Using subclassing to bung in some arbitrary trait is really terrible.
:/  It requires either adding it up high in your class hierarchy, or
having to write a custom NoSuchPropertyClass which extends your
superclass, so you can then extend it.

I'm rather surprised that the group actually considered that sort of
code to be appropriate - it's known that it doesn't compose well with
other traits-as-superclasses or normal subclassing.


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