public Contact(string name, DUnion <EmailAddress, PostalContactAddress> primary, DUnion <EmailAddress, PostalContactAddress>?secondaryContact = null)//Nullability is the "NEW" optional provided u are comfortable with C# 8 nullable options
{
Name = name;
PrimaryContact = primary;
SecondaryContact = secondaryContact;
}
DUnion(DUnion<T1, T2, T3> source)
: this(source.Discriminator, source.CoproductValue)
{
}
