When dealing with Tokio and futures, the futures passed to the Tokio runtime must have a 'static lifetime most of the time. I understand that because the future might be moved to another thread where it can potentially outlive the place it was defined.
There is a method Runtime::block_on_all which guarantees that the future called will be terminated by the end of the call, it even returns the result of running this future.
In that case, I don't get (except for simplicity of the Tokio code) why the future must be 'static.
Can anyone shed some light on this?