operator + method
Implementation
OptionalList<T> operator +(final OptionalList<T> that) {
return bothPresent<List<T>, List<T>, List<T>>((a, b) => a.followedBy(b).toList())(this, that);
}
OptionalList<T> operator +(final OptionalList<T> that) {
return bothPresent<List<T>, List<T>, List<T>>((a, b) => a.followedBy(b).toList())(this, that);
}