Serialize: enum members

[Inkrementator]

Currently, enum members of a composite type are ignored

struct S {
    int i = 0;
    enum foo = "bar";
}
S(5).serialize.writeln() // {"i": 5}

std.traits.FieldNameTuple is used to get the members. Afaik, there is nothing in std.traits to get enum "members". Traits has allMember which would work.

Deserialize could either automatically ignore enums or check them for correctness.

[schveiguy]

Unsure how I feel about this. Why serialize an enum?

On the other hand, this should be configurable. Every time I look at serialization here, it screams for a customizable policy.

[Inkrementator]

Why serialize an enum?

This isn't really useful for commicating with code that you control. But it allows designing slightly cleaner APIs/ omitting some boilerplate when all you ever do is serialize something, i.e. talking to some external REST api via json.

Let's take the toy example from wikipedia and zoom in on the balance field

"balance": {
            "currency": "usd",
            "value": 100.00
        }

For my program, I know that currency will always be "usd", so I could just define this struct as my D API:

struct Balance {
    enum currency = "usd";
    float value;
}

This is more convenient than the alternative of having to write a custom toJSON or finding an unidiomatic way to make sure that this field only ever takes a specific value and isn't set by a user of my code.

[schveiguy]

Yeah OK, that's a good use case.

[schveiguy]

Another thing to think about is static members. I suppose you can just label them @ignore if needed.