Code:
#include <CustomStepper.h>

enum stepper_e { ST_VL, ST_HL, ST_VR, ST_HR, ST_MAX };

CustomStepper motoren[ST_MAX]
{
  CustomStepper(22, 24, 26, 28),
  CustomStepper(23, 25, 27, 29),
  CustomStepper(47, 49, 51, 53),
  CustomStepper(46, 48, 50, 52)
}