Unwrap twice

[van-sprundel]

Hey, love the concept!

Had a question about the following snippet:

while let Some(todo) = todos.next().await {
    let todo = todo.unwrap();
    ...
}

I was curious why the design makes it necessary to unwrap twice. Can an item exist but be invalid?

[carllerche]

There is only one unwrap there? I think it is because next() returns Option<Result<_>>. The Option returning None indicates the stream is empty. Result tracks if there is an error or not.