That’s not the fault of fmt.Errorf(); if you aren’t giving people a type or a value to compare against there’s nothing the standard library can do to help you.

That’s not the fault of fmt.Errorf(); if you aren’t giving people a type or a value to compare against there’s nothing the standard library can do to help you. You need to try string matching or maybe reflection. The standard library can’t fix bad code. Thankfully I don’t share your experience with people commonly returning those kinds of errors (at least not where one needs to match against an error).