Extending Enum in Ada

Question

Is it possible to extend an Enum type in Ada? if I have for example:

type ABC_Type is (A, B, C);

Now I want new type ABCDE_Type that will include everything that ABC_Type has and Also (D, E). Is there a way to do that?

Answer 1

No, you cannot extend an Enum type in Ada, you can only create derivations/subtypes that cover a subset of the original one.

You have to do it the other way round:

type ABCDE_Type is (A, B, C, D, E);
type ABC_Type is new ABCDE_Type range A .. C;
-- or
subtype ABC_Type is ABCDE_Type range A .. C;