serde.rs

impl<'de, T> Deserialize<'de> for Message<T>
where
    T: Deserialize<'de>,
{
    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
    where
        D: Deserializer<'de>,
    {
        struct Visitor<'de, T>(PhantomData<T>, PhantomData<&'de ()>);
        impl<'de, T> serde::de::Visitor<'de> for Visitor<'de, T>
        where
            T: Deserialize<'de>,
        {
            type Value = Message<T>;
            fn expecting(
                &self,
                formatter: &mut serde::export::Formatter,
            ) -> serde::export::fmt::Result {
                serde::export::Formatter::write_str(formatter, "Message")
            }
            #[inline]
            fn visit_seq<A>(self, mut seq: A) -> Result<Self::Value, A::Error>
            where
                A: SeqAccess<'de>,
            {
                // Custom error here if the magic number is not correct
                let magic_number = seq.next_element::<u32>()?;
                let data = seq.next_element::<T>()?;
                let data = data.unwrap();
                Ok(Message { data })
            }
        }
        deserializer.deserialize_tuple_struct("Message", 2, Visitor(PhantomData, PhantomData))
    }
}