make_ready_future for move-only types

[dixlorenz]

This code fails to compile:

auto f = stlab::make_ready_future(std::make_unique(4));

Judging from stlab::async, the return in make_ready_future should probably be

return std::move(p.second);

[FelixPetriconi]

Many thanks for spotting this. We will fix it with the next patch.

[FelixPetriconi]

Fixed in 1.4.1