Make (vec) conversions more general

[icefoxen]

Specifically, it seems like JsonValue should implement: impl From<Vec<T>> for JsonValue where T: Into<JsonValue> , or something along those lines. The goal would be to implement a new type, do impl From<MyType> for JsonValue, and be able to convert a Vec<MyType> to JsonValue automatically.

There may be analogous conversions possible for containers other than Vec, I can't think of any specific ones right now though.

[icefoxen]

Proof of concept:

#[derive(Debug)]
enum JsonValue {
    Integer(i32),
    Array(Vec<JsonValue>),
}

impl From<i32> for JsonValue {
    fn from(value: i32) -> JsonValue {
        JsonValue::Integer(value)
    }
}


impl<T> From<Vec<T>> for JsonValue where JsonValue: From<T> {
    fn from(value: Vec<T>) -> JsonValue {
        let new_values = value.into_iter().map(From::from).collect();
        JsonValue::Array(new_values)
    }
}


struct MyType(i32);
impl From<MyType> for JsonValue {
    fn from(value: MyType) -> JsonValue {
        JsonValue::Integer(value.0)
    }
}


fn main() {
    let myvalues = vec![MyType(1), MyType(2), MyType(3)];
    let json_array: JsonValue = From::from(myvalues);
    println!("Json array is: {:?}", json_array);
}

[maciejhirsz]

This makes perfect sense. I'll try to sneak it in on Sunday.