Reading the same code I also cringed, but for a different reason: the validity of `paths` is tied to the validity of `err`; you should never look at at `paths` without first checking `err`. We can solve this much better using sum types (also known as discriminate unions):

    // Pseudo Go:
    maybe_paths := filepath.Glob(dir + "/*.png")
    case maybe_paths of {
      Some paths: {
        // Do things with paths
      }
      None: {
        // Handle error case
      }
    }

This makes it impossible to use `paths` if `Glob` returns an error, as `paths` won't be in scope!

Furthermore, not having sum types forces us to include a distinguish value `null` for reference (pointer) types, as a way to communicate "no value". This is bad as now we cannot distinguish references that should never be `null` from those than can be `null`.