Send + 'static trait requirements? about futures-rs HOT 3 CLOSED

Thanks for the issue! I've added an FAQ to the main repository as I suspect there'll be quite a few questions along these lines! And this is now the first answered question.

If you have more thoughts on that, though, please feel free to ask here!

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I'm not so concerned about Send, but more about 'static. The fact that futures are static means that it is almost mandatory to use Arcs everywhere.

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Ah interesting! We've discussed a few times how we might get rid of 'static, but unfortunately it always seems to end up akin to "add a lifetime parameter everywhere", which to us seems like it's not worth the ergonomic cost.

Another way to think about it is that if you were writing an event loop by hand, all lifetimes of borrowed objects which persist across event loop iterations have to live longer than the event loop itself, and that's the lifetime that would get threaded everywhere.

In general though the cost of an allocation for 'static data shouldn't be too bad as it's only required once per task, not once per future or once per poll or anything like that.

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