If you assume it's not concurrent when it is, that's the programmer's fault. This is true of both goroutines and threads in equal capacity; distinguishing betwe

If you assume it's not concurrent when it is, that's the programmer's fault. This is true of both goroutines and threads in equal capacity; distinguishing between the two won't stop that from happening. If you assume it is concurrent when it isn't, nothing bad happens. The point of 'function color' is that hiding it implies it needs to be shown, which it doesn't. Rust hides from you which register a local variable is stored in, because it is thoroughly irrelevant to you and exposing it would require you to care when Rust is perfectly capable of managing it for you. There are legitimate reasons to prefer a colored approach to asynchrony. But the two points are good points and you should prefer the colored approach only when said legitimate reasons outweigh those points given the language's design.