Comment by watt

12 hours ago

If they're not going to handle the return values, they should change the function signature to reflect this aspirational contract, that that function "never fails".

I see in the article they did change the poll_flush to run just-in-time at poll_shutdown. So they definitely can make a "best effort" poll_flush version that just does not return any errors for use in that loop.

But all in all? Amateur hour.

3 comments

watt

a_cul 11 hours ago

You're missing how rust works. The function is explicitly allowed to fail, which is why it returns a Result<(), Error>. They're using the function calls within for their side effects. The ? at the end of each line signals that the function will short-circuit return with an error if the function call fails, and only if it is successful it returns the actual value: they just don't care about this value, hence the let _ =. Basically, they are doing the equivalent of:

  let _, err = function_call();
  if err {
    return err
  }
  ...

watt 10 hours ago
What I am saying, is make another version of the function, which is explicitly not allowed to fail, if you want to use it in the loop.