Deserializers composition

[xamgore]

Let's say I have a struct A, which can be deserialized from u8.

#[repr(u8)]
#[derive(Deserialize_repr)]
enum A {
  Variant = 12,
}

And I have JSON data, where the field is presented as an integer in a string:

{
  "field": "12"
}

I'd like to extract the field through the sequence of deserializers: str -> u8 & u8 -> A. How can I do it? (We can assume Serialize_repr is also implemented)

#[serde_as]
#[derive(Deserialize)]
pub struct Data {
  #[serde_as(as = "...")]
  field: A,
}

The best approach I could find was JsonString<Same>, which is a bit off.

#[serde_as(as = "JsonString<_>")]
field: A

[jonasbb]

Why are you deriving a wrong Deserialize implementation in the first place? If you want the enum to serialize into strings with decimal numbers, the Deserialize implementation should match that. The normal serde_derive is enough to achieve that:

#[repr(u8)]
#[derive(serde::Serialize)]
enum A {
    #[serde(rename = "12")]
    Variant = 12,
}

If you don't like the way JsonString is implemented, you could write something yourself. There is nothing in the serde_with crate, that will allow you to chain deserializing behavior like str -> u8 & u8 -> A.

[xamgore]

Hmm, that's nice, thanks! 👍🏻 Never had an idea of renaming variants.