What is wrong with the way I am trying to using the join!
macro in the code at the link at the bottom?
The error is "(std::result::Result<f64, std::io::Error>, std::result::Result<f64, std::io::Error>)
is not a future". But what I'm doing seems to match what I see in this blog:
in the line join!(first_sleeper(), second_sleeper());