/**
  * @brief Get a reference to a singleton instance of this Type.
  *
  * @param nullable Whether to get the nullable version of this Type.
  * @return A reference to the desired singleton instance of this Type.
  **/
 static const IntType& Instance(const bool nullable) {
   if (nullable) {
     return InstanceNullable();
   } else {
     return InstanceNonNullable();
   }
 }
 /**
  * @brief Get a reference to a singleton instance of this Type.
  *
  * @param nullable Whether to get the nullable version of this Type.
  * @return A reference to the desired singleton instance of this Type.
  **/
 static const DatetimeIntervalType& Instance(const bool nullable) {
   if (nullable) {
     return InstanceNullable();
   } else {
     return InstanceNonNullable();
   }
 }
 const Type& getNullableVersion() const {
   return InstanceNullable();
 }