// FormatError calls the FormatError method of f with an errors.Printer // configured according to s and verb, and writes the result to s. func FormatError(f Formatter, s fmt.State, verb rune) { … } var detailSep … type state … func (s *state) Write(b []byte) (n int, err error) { … } type printer … func (s *printer) Print(args ...interface{ … } func (s *printer) Printf(format string, args ...interface{ … } func (s *printer) Detail() bool { … }