compiler option: target platform

Question

compiler option: target platform

aeosynth opened this issue 11 years ago · 7 comments

say i'm building a mobile app, and have access to all the latest js features; i'd like to pass a flag to the compiler, telling it to use those features instead of shims

Answer 1 · 2013-03-13T20:07:17.000Z

Good "shims" are usually faster than the native implems, I remember @jdalton 's talk about that.

Answer 2 · 2013-03-13T20:08:19.000Z

so keep the fast shims

Answer 3 · 2013-03-15T14:06:52.000Z

To clarify, if you're using newer native methods, and then wanting to support browsers that don't have them, your shims should follow the spec. This will make them slower, but necessary if you are putting shims onto Array.prototype or other builtins.

To keep things speedy I've used utility methods instead that can opt-in to native use when it's proven faster for given environments. This allows me to avoid following spec so close that it hurts perf for fallbacks while getting the speed of native when it's relevant.

Answer 4 · 2013-03-15T14:24:05.000Z

We quit simulating [].indexOf for similar reasons.

Answer 5 · 2013-03-15T16:32:28.000Z

are there any shims coco uses which have worse performance than native methods? if not, this issue can be closed as pointless

Answer 6 · 2013-03-15T17:31:45.000Z

are there any shims coco uses which have worse performance than native methods?

None atm I believe.

if not, this issue can be closed as pointless

Alrighty.

Answer 7 · 2013-03-15T17:39:15.000Z

If you point me to the file w/ the shims I can do a quick review as well.