My ECMAScript 7 wishlist

André Bargull andre.bargull at
Sat Jun 7 01:42:47 PDT 2014

> that `has:()=>true` breaks with features detections that are meant to be
> less obtrusive than getters ... i.e. `'geolocation' in navigator` or
> `'innerHTML' in genericNode` and all others that are not supposed to pass
> through a potentially expensive getter to retrieve a feature detection
> purpose info.
> Long story short that NoSuchProperty is obtrusive in an upside-down way ...
> I personally would not use that and would not expect that anywhere

The 'has' handler is required to work around a Firefox limitation. A 
compliant ES6 implementation only needs the 'get' handler.

Related bug reports:

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