Automatically implement from using default

[vic1707]

Via an attribute ?

[vic1707]

The idea would be to do

struct FooV0 {
    name: String,
}

#[derive(Deserialize)]
#[versioning(from_default, previous_version = "FooV0")]
struct FooV1 {
    name: String,
    age: u8,
}

and get the Deserialize impl generated as well as a

impl From<FooV0> for FooV1 {
    fn from(value: FooV0) -> Self {
       /* insert all fields from value */
        ..Default::default()
    }
}

unfortunately

impl From<FooV0> for FooV1 {
    fn from(value: FooV0) -> Self {
        ..value,
        ..Default::default()
    }
}

Isn't valid rust.

[vic1707]

Would probably only be available for structs with named fields 🤔

[vic1707]

don't think its possible, at least with my current knowledge

Best i could get was to generate

impl From<FooV2> for Foo {
    fn from(value: FooV2) -> Self {
        Self {
            name: value.name,
            age: value.age,
            place_holder: value.place_holder,
            ..Default::default()
        }
    }
}

but this is generated from the fields of Foo, not FooV2, so I assign place_holder which doesn't exist on FooV2 => error.
Try is here : 0c5e5c2

[vic1707]

https://docs.rs/serde-reflection/latest/serde_reflection/
Might help ?