Strings in VEXcode functions?

Programming Support VEXcode Pro V5 Text Tech Support
#1

So, i want to make a simpler way to make basic controls through a function, i want to make strings which you input into the function like group which you put in a motor group, or button where you put in a controller button.
How would i go about doing this, i tried std::string for each one but that didn’t work because i couldn’t substitute them into the actual commands.

#2

Yes you can use strings as an argument to a function but it is not very efficient.

This is an example of what you are asking:

void drive(std::string action, int value)
{
  if( action=="forward" )
  {
     motorL.spin(fwd, value, pct);
     motorR.spin(fwd, value, pct);
  }
  else if( action=="reverse" )
  {
     motorL.spin(rev, value, pct);
     motorR.spin(rev, value, pct);
  }
  else if( action=="turnLeft" )
  {
     motorL.spin(rev, value, pct);
     motorR.spin(fwd, value, pct);
  }
  else if( action=="turnRight" )
  {
     motorL.spin(fwd, value, pct);
     motorR.spin(rev, value, pct);
  }
  else if( action=="stop" )
  {
     motorL.stop(brake);
     motorR.stop(brake);
  }
}

void autonomous()
{
   drive("forward",50);
   vex::task::sleep(1000);
   drive("turnLeft",30);
   vex::task::sleep(500);
   drive("stop");
}

Better way of passing commands is enum:

enum driveEnum { 
 eStop = 0,
 eDriveTime = 1,
 eTurnTime = 2,
 eDriveDistance = 3,
 eTurnDistance = 4
};

void drive(driveEnum action, int value, int howLong)
{
   if( action==eStop )
   {
      motorL.stop(brake);
      motorR.stop(brake);
   }
   else if( action==eDriveTime ) // positive value drives forward, negarive backward
   {
      motorL.spin(fwd, value, pct);
      motorR.spin(fwd, value, pct);
      if( howLong != 0 )
           vex::task::sleep(howLong);
   }
   else if( action==eTurnTime )  // negative value turns to the left, positive to the right
   {
      motorL.spin(fwd, value, pct);
      motorR.spin(rev, value, pct);
      if( howLong != 0 )
           vex::task::sleep(howLong);
   }
   else if( action==eDriveDistance ) // positive howLong drives forward with value speed, negarive backward
   {
      motorL.spinFor( howLong, deg, value, pct, false); // don't wait
      motorR.spinFor( howLong, deg, value, pct, true);  // wait for completion
   }
   else if( action==eTurnDistance ) // positive howLong turns to the right with value speed, negarive to the left
   {
      motorL.spinFor(  howLong, deg, value, pct, false); // don't wait
      motorR.spinFor( -howLong, deg, value, pct, true);  // wait for completion
   }
}

void autonomous()
{
   drive(eDriveDistance, 50, 500); // vel=50 pct, distance=500 deg
   drive(eTurnDistance, 30, -200); // vel=30 pct, turn left=200 deg in wheel units, not robot units
   drive(eDriveTime, -50, 1000); // drive back with vel = 50 for 1 sec
   drive(eStop);
}

Motor command reference: https://api.vexcode.cloud/v5/html/classvex_1_1motor.html

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