operator - method

num? operator -(num other)

Subtraction operator.

If the current value is not null, subtracts other from it, updates the value, and returns the new value. If the current value is null, returns null.

Implementation

num? operator -(num other) {
  if (value != null) {
    value = value! - other;
    return value;
  }
  return null;
}