Not all errors are "exceptional". For example, consider an API that lets you open a file (local or remote); it may be very common that a file doesn't exist and

Not all errors are "exceptional". For example, consider an API that lets you open a file (local or remote); it may be very common that a file doesn't exist and it may be natural to handle that case by checking a "file not found" error (checking if the file exists before accessing it incurs in an extra cost and it's also racy).