code: func JoinSchemeNamePort(scheme, name, port string) string {
  	if len(scheme) > 0 {
  		// Must include three segments to specify scheme
  		return scheme + ":" + name + ":" + port
  	}
  	if len(port) > 0 {
  		// Must include two segments to specify port
  		return name + ":" + port
  	}
  	// Return name alone
  	return name
  }
docs: // JoinSchemeNamePort returns a string that specifies the scheme, name, and port:
  //  * "<name>"
  //  * "<name>:<port>"
  //  * "<scheme>:<name>:<port>"
  // None of the parameters may contain a ':' character
  // Name is required
  // Scheme must be "", "http", or "https"