Le 20/04/2013 15:17, Brendan Eich a écrit :
> Tab Atkins Jr. wrote:
>> It would be so nice if JS had multiple return values, so we could let
>> cancellable future-returning APIs just return a naked resolver as
>> their second value,
>
> Hello, destructuring:
>
> let{  proxy, revoke}  = Proxy.revocable(target, handler);
>
>
> from 
> http://wiki.ecmascript.org/doku.php?id=strawman:revokable_proxies. Or 
> use an array pattern if you prefer.
>
> JIT'ing VMs can optimize these pretty easily to avoid object allocation.
I find pretty interesting cases where high-level expressive syntax 
results in optimizations that were impossible to very hard without the 
syntax.
Is it already implemented in SpiderMonkey? If not, is there a bug number 
to follow the progress?

Thanks,

David

Le 20/04/2013 15:17, Brendan Eich a ?crit :
> Tab Atkins Jr. wrote:
>> It would be so nice if JS had multiple return values, so we could let
>> cancellable future-returning APIs just return a naked resolver as
>> their second value,
>
> Hello, destructuring:
>
> ```js
> let{  proxy, revoke}  = Proxy.revocable(target, handler);
> ```
>
>
> from 
> http://wiki.ecmascript.org/doku.php?id=strawman:revokable_proxies. Or 
> use an array pattern if you prefer.
>
> JIT'ing VMs can optimize these pretty easily to avoid object allocation.

I find pretty interesting cases where high-level expressive syntax 
results in optimizations that were impossible to very hard without the 
syntax.
Is it already implemented in SpiderMonkey? If not, is there a bug number 
to follow the progress?

Thanks,

David