Recently, we were examining some ill-structured code that called (Context).Err() without first calling (Context).Done(). Typically, this seems to return a nil error without any guarantees as to what that means, but this doesn't seem to be called out explicitly.
Should it be required to call Done() before Err()? What should the behavior of Err() called before Done() be in compliant implementations? I understand the obvious answer is "don't do this", but this seems to be a common mistake and the description of the methods don't make this relationship clear. Is more documentation required? This came up in the context of this discussion: https://github.com/docker/swarmkit/pull/1437#issuecomment-242892988. The thought was that we could mostly remove the need for a lock on the err field if Done() always provides a barrier. However, incorrect usage of the interface would lead to racy results if the field is unprotected. Cheers, Stephen. -- You received this message because you are subscribed to the Google Groups "golang-nuts" group. To unsubscribe from this group and stop receiving emails from it, send an email to golang-nuts+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
