Are there any proposals for Tuples?
Le 03/04/2013 17:54, BelleveInvis a écrit :
I mean, a stack-allocated, immutable, simple, value type, for high-performance uses.
I think binary data [1] is very close to what you're looking for. "stack-allocated" is complicated to ask. It really depends on what the JS "interpreters" decides to do with your variable and I don't think having a construct to express "put that on the stack" would be appropriate for such a high-level language.
David
Yeah, I wrote brendaneich.com/2011/01/harmony-of-my-dreams which included tuples, but after an initially warm reception, TC39 settled down to more incemental moves, and binary data emerged.
We've been thinking along the following lines since then, apologies for brevity:
With new Uint32Array(4) you get a reference type instance. Just as with typed arrays today, but same goes for structs as for arrays.
With Uint32Array(4) -- note lack of 'new' oeprator -- you would get an immutable value type, which could be stack allocated if escape analysis allows. This is for the VM to worry about. It's the JS way.
On Wed, Apr 10, 2013 at 6:48 PM, Brendan Eich <brendan at mozilla.com> wrote:
Yeah, I wrote brendaneich.com/2011/**01/harmony-of-my-dreamsbrendaneich.com/2011/01/harmony-of-my-dreamswhich included tuples, but after an initially warm reception, TC39 settled down to more incemental moves, and binary data emerged.
We've been thinking along the following lines since then, apologies for brevity:
With new Uint32Array(4) you get a reference type instance. Just as with typed arrays today, but same goes for structs as for arrays.
With Uint32Array(4) -- note lack of 'new' oeprator -- you would get an immutable value type, which could be stack allocated if escape analysis allows. This is for the VM to worry about. It's the JS way.
I like where this is going. But how did the array returned by Uint32Array(4) get initialized?
Could these be the same as the ParallelArrays used by rivertrail? They can be safely shared between workers for the same reason they can be safely shared between threads within an event loop.
Mark S. Miller wrote:
On Wed, Apr 10, 2013 at 6:48 PM, Brendan Eich <brendan at mozilla.com <mailto:brendan at mozilla.com>> wrote:
Yeah, I wrote http://brendaneich.com/2011/01/harmony-of-my-dreams/ which included tuples, but after an initially warm reception, TC39 settled down to more incemental moves, and binary data emerged. We've been thinking along the following lines since then, apologies for brevity: With new Uint32Array(4) you get a reference type instance. Just as with typed arrays today, but same goes for structs as for arrays. With Uint32Array(4) -- note lack of 'new' oeprator -- you would get an immutable value type, which could be stack allocated if escape analysis allows. This is for the VM to worry about. It's the JS way.I like where this is going. But how did the array returned by Uint32Array(4) get initialized?
Same as with typed arrays today:
js> a = Uint32Array(4) ({0:0, 1:0, 2:0, 3:0})
Could these be the same as the ParallelArrays used by rivertrail? They can be safely shared between workers for the same reason they can be safely shared between threads within an event loop.
This seems possible, but I defer to Dave, Niko, and Rick.
I mean, a stack-allocated, immutable, simple, value type, for high-performance uses.