Deriving from an enum in C++

Question

Is it possible to derive from an enum, if so how?

For instance:

enum eStandardTypes
{
    Type1 = 0,
    Type2,
    Unknown,
    Count,
};

enum eExtendedTypes : eStandardTypes
{
    Type3 = eStandardTypes::Count,
    Unknown,
    Count,
};

Upvoted for intrigue. If it was good enough for a C++ standards discussion, then it's good enough to be asked here. — Bathsheba, Jul 24 '17 at 09:00
@GainPaolo Did the search, nothing popped up that looked like this question, but it sure does look like a duplicate. — Tim, Jul 24 '17 at 09:04
@GianPaolo you dont need to "downvote as duplicated" but just flag the question. Imho being a duplicate isnt a reason for downvote — 463035818_is_not_an_ai, Jul 24 '17 at 09:04
@tobi303: Especially given that the OP clearly is not au fait with the terminology; do study the question edits. — Bathsheba, Jul 24 '17 at 09:05
Can't create a class as showned at the [stated duplicate as](https://stackoverflow.com/a/644639/7880546) because of I am using an external (open sourced) library. That would break the conventions of that library. Made a comment as I agree on the duplicate. Gave me the answer too. — Tim, Jul 24 '17 at 09:15

score 6 · Accepted Answer · answered Jul 24 '17 at 08:59

6

No this is not possible, even with enum classes.

Support for inheritance of enum classes was discussed for C++17, but was not incorporated into that standard.

answered Jul 24 '17 at 08:59

Bathsheba

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Deriving from an enum in C++

1 Answers1