Driver Station I/O in C++

[AndrewD]

Hello all,
I'm trying to read buttons from the cypress board to fire relays on the 'bot.
My code so far (just for the relays and dsio) is:

class RobotDemo : public SimpleRobot
{
     Relay barrel1;
     Relay barrel2;
     Relay barrel3;
     DriverStation ds;

public:
     RobotDemo(void):
          barrel1(3),
          barrel2(4),
          barrel3(5),
          ds()
     {
           GetWatchdog().SetExpiration(0.1);
     }
     void OperatorControl(void)
     {
          GetWatchdog.SetEnabled(true);
          while (IsOperatorControl())
          {
               GetWatchdog().Feed();
               if (ds.GetDigitalIn(3)) {
                    barrel1.Set(Relay::kOn)
               } else {
                    barrel1.Set(Relay::kOff)
               }
          }
     }
}

of course there is more code for the drive train but this is all that needs help. i need to know what to put in the parentheses for "ds()" under "RobotDemo(void):"

Thanks in advance,
Andrew D.

[byteit101]

If I did not know WPILib, your question is already answered (that is where you put the parens). However, I do know WPILib, and you are initializing the ds wrong (because you are getting an error you did not post, which are helpful, no matter how odd it may seem to you). The DS is a singleton, and so you need to initialize it based on the singleton. If you looked at the WPILib docs, you would notice the constructor is private.

..
     Relay barrel3;
     DriverStation &ds;

public:
     RobotDemo(void):
          barrel1(3),
          barrel2(4),
          barrel3(5),
          ds(*(DriverStation::GetInstance()))
     {
           GetWatchdog().SetExpiration(0.1);
     }
     void OperatorControl(void)
...