code: func (e parseError) Error() string {
  	var buf bytes.Buffer
  	buf.WriteString("parse error: ")
  	buf.WriteString(e.message)
  	if f := e.file; len(f) > 0 {
  		buf.WriteString(" in file ")
  		buf.WriteString(f)
  	}
  	buf.WriteString(" at line ")
  	buf.WriteString(strconv.Itoa(e.line))
  	buf.WriteString(" column ")
  	buf.WriteString(strconv.Itoa(e.col))
  	if e.eof {
  		buf.WriteString(" (at EOF)")
  	}
  	buf.WriteString("\n    ")
  	buf.WriteString(e.context)
  	return buf.String()
  }
docs: // Error returns the formatted string representation of this parse error.