Type safe promises prototype

[ibaca]

Discussion https://groups.google.com/forum/#!topic/gwtquery/mMey1XVkNGM

I don't add types for failures and progress because I prefer a simpler solution. Also, I propose the Zip strategy (https://github.com/ReactiveX/RxJava/blob/1.x/src/main/java/rx/Observable.java#L2639) because it's solves the problem whitout add complex generics in Promise interface.

Related project https://github.com/jdeferred/jdeferred, this project is an example of full typesafe promises. Although I think that add the failure type as generic is a bad idea (unnecessary complexity), I vote for failures to be Thorwables (reactivex strategy).

[jDramaix]

Thanks for the contribution and sorry for the delay. I let Manolo handle this PR

[manolo]

@ibaca I have a meeting with @jDramaix next week, I guess we can talk about this patch. Basically I want to talk in a more general way how to deal with Function in gQuery and prepare it to use j8 lambdas, this patch definitively is a good reference.

[jDramaix]

@manolo I think we can close this ?

@ibaca The idea is to prepare Function in order to be able to use java 8 lambda instead.

[ibaca]

Ok, one final thought :wink: (I see this the other day, I want to leave the link here) and you can close it.

This tuple strategy https://github.com/reactor/reactor/wiki/Tuples might be interesting, so the Deferred and Promise can be implemented of one type T, and the current Function.argument(N) methdods might be implemented as a extension of TupleN with the auto-cast mehtod argument(N). Ex:

class Arguments extends TupleN {
  public <T> T argument(int index) { return (T) get(index); }
}
// so all current internal gwtquery promises usages will looks like
Promise<Arguments> promise = ...

[manolo]

@ibaca, as Julien says we want function interfaces in all places where Function is used, not only in promises, could we take this code as base? are you interested on contributing? If you have a while we could have a meeting, I guess you are in Spain as me so we can speak Spanish :-)

[ibaca]

@manolo, you can use this as a code base, although be careful with Functions that is almost copied from rxjava. You probably need to prototype other strategies so probably Functions is not needed finally. I'm interested in contributing, but I cannot compromise. I have some difficulties with English :open_mouth:, so meetings in Spanish are always welcome. I'm also in the irc #GWT channel.

[olafleur]

Last commit was more than 6 months ago. Closing. Feel free to reopen a pull request as needed.