On Mar 2, 2015, at 9:30 AM, John Lenz wrote:
> I was recently discussion Promise optimizations (specifically, that in any
> "then" chain at least one Promise object is created that goes unused), this
> could be solved by some metadata that indicated whether the result of the
> function would be consumed:
> ...
> if (function.called_from_void_result_context) {
> ...
> I'm not really sure what impact this would have on the VMs but I found it an
> interesting idea.
Essentially, this means that an additional implicit parameter
("calledForValue") needs to be added for every function call. At the MOP level
this would manifest as an extra argument to the [[Call]] internal method. It
could be defined to default to true and implementation could probably optimize
for the default case. But, at least conceptually it requires passing
additional information across the call boundary. that might be a bit much if
this is only about optimizing promises.
Allen
_______________________________________________
es-discuss mailing list
[email protected]
https://mail.mozilla.org/listinfo/es-discuss
