Maybe so, but having exceptions in a language is also a good predictor for the misuse of exceptions for purposes other than error handling. For instance, Python has the StopIteration exception to signal the end of an iteration.

Exceptions force API designers to decide whether or not a situation is exceptional enough to force a stack unwind on the caller's end. That's not something that's necessarily decidable from the point of view of the library.

For instance, say you have a function http.get(url). Should a 404 response automatically raise an exception? What about a 301? A network issue? Surely, for a crawler, a 404 is not exceptional enough to merit a hidden goto that unwinds the stack frame (by default). The designer of the http library cannot decide which status code is exceptional in every application.

It's similar with the results of SQL statements, file system access and all sorts of other IO related stuff.

It seems to me that the more complex a system is, the more it needs a very specific error handling strategy anyway and doesn't benefit from library designers' opinions about what is and isn't worth a stack unwind.

That said, I do hate seeing

  if err != nil {
    return nil, err
  }