
  [;1m-spec '+'(number()) -> number().[0m

  The documentation for '+'/1 is hidden. This probably means that
  it is internal and not to be used by other applications.

  [;1m-spec '+'(number(), number()) -> number().[0m

  The documentation for '+'/2 is hidden. This probably means that
  it is internal and not to be used by other applications.
