future module is confusing, as is relationship to task

[jesse99]

Wanted to use a future and I was quite confused looking at the task module until I started examining the implementation. It would help a lot if fn future_result and probably fn try pointed people to the future module.

[brson]

I would like to remove task's dependency on future completely. I think that future_result could just as easily return a port, though I haven't looked at it lately. Then future can move to std.

[brson]

Also, future_result needs a different interface. It's awkward and deadlock prone.

[brson]

See also #2491

[nikomatsakis]

Not critical for 0.6; removing milestone

[graydon]

Future is currently in extra (nee std) and task::future_result currently produces a Port<TaskResult> for the caller to listen on (the function should probably be renamed).

extra::future does not seem terribly complex an interface anymore. Maybe this was filed back when it was more so?

[graydon]

closing as too-vague. specific enhancements welcome.