How can I pass multiple variables to a function? Using the FastLED library, I want to light up multiple lights at once. 

Currently I am passing in just one light to the function. 

spell( int LEDNumber )
{
  FastLED.clear();
  leds[LEDNumber] = CRGB (255,255,255); //white
  FastLED.show();
  time = 500;
  delay(t);
}


I would like to pass in more than just 1 light at a time.
You may create a struct with "x" elements, one for each LED:

struct ArrayOfBooleans {
   bool array[4];
};

ArrayOfBooleans myOutputArray;
myOutputArray.array[0] = true;
myOutputArray.array[1] = true;
myOutputArray.array[2] = false;
myOutputArray.array[3] = true;

lightEmUp(myOutputArray);

void lightEmUp(ArrayOfBooleans myOutputArray) {
   bool isFirstLightOn = myOutputArray.array[0];
   // etc
}


NoTE: If you run into Exception 9 issues (using this logic on another board), please check this answer to another post