I'm not sure I understand you, or you understand me. I'm saying this is okay:
type Order struct {
Type OrderType
CommonAttr1 int
CommonAttr2 string
}
type OrderTypeA struct {
Order
TypeAAttr1 int
TypeAAttr2 string
}
type OrderTypeB struct {
Order
TypeBAttr1 int
TypeBAttr2 string
}
And yes you should convert to OrderTypeA or OrderTypeB at the first opportunity in domain code, and only convert from them at the latest opportunity.
You seem to be under the impression that I'm advocating for something like
type OrderUnion struct {
CommonAttr1 int
CommonAttr2 string
TypeAAttrs
TypeBAttrs
}
That's what I consider going crazy.
