operator % method
Euclidean modulo operator.
Returns the remainder of the Euclidean division. The Euclidean division of
two integers a and b yields two integers q and r such that
a == b * q + r and 0 <= r < b.abs().
The Euclidean division is only defined for integers, but can be easily
extended to work with doubles. In that case r may have a non-integer
value, but it still verifies 0 <= r < |b|.
The sign of the returned value r is always positive.
See remainder for the remainder of the truncating division.
Implementation
num? operator %(num other) {
  if (value != null) {
    return value! % other;
  }
  return null;
}