Support adjacently tagged enum but with content name equals to tag

[WiSaGaN]

I have:

{"type":"function","function":{"name":"foo","parameters":"bar"}}
{"type":"search","search":{"keyword":"foo"}}

I want them to be deserialized into

#[derive(Deserialize, Serialize)]                                            
#[serde(tag = "type", content = tag)] // Not supported now
#[serde(rename_all = "snake_case")]
enum Tool {
    Function(Function),
    Search(Search),
}
#[derive(Deserialize, Serialize)]
struct Function {
    name: String,
    parameters: String,
}
#[derive(Deserialize, Serialize)]
struct Search {
    keyword: String,
}

And also these structs serialized into those.

Motivated by OpenAI API: https://platform.openai.com/docs/api-reference/chat/create functions

Currently we can get around using below

#[derive(Deserialize, Serialize)]
#[serde(tag = "type")]
enum Tool {
    Function {
        function: Function,
    },
    Search {
        search: Search,
    },
}

But would be much cleaner and avoid inconsistent data if we have native support.

[alteous]

I would also like to see this feature. This structure is used in glTF, notably by cameras:

{
    "name": "Finite perspective camera",
    "type": "perspective",
    "perspective": {
        "aspectRatio": 1.5,
        "yfov": 0.660593,
        "zfar": 100,
        "znear": 0.01
    }
}

[andrewtoth]

From your example it seems like the type field can be skipped for deserialization and then just use the default externally tagged enum representation?

[WiSaGaN]

From your example it seems like the type field can be skipped for deserialization and then just use the default externally tagged enum representation?

Yes, it would work in that case for deserialization, but would be trickier for serialization.

[luminosoda]

Found this awesome crate https://github.com/de-vri-es/serde-double-tag