serialization - Can I implement the same trait multiple times in different ways for a single struct? -


i'd serialize struct in 2 different ways depending of situation i'm facing problem: current knowledge can serialize struct in 1 way.

here code #[derive(serialize)] (auto derive)

#[derive(serialize, deserialize, partialeq, debug)] struct transactioncontent {     sender_addr: vec<u8>,     sender_pubkey: vec<u8>,     receiver_addr: vec<u8>,     amount: u32,     timestamp: i64 }

i'm using bincode::serialize serialize struct , make vec<u8> , also want store struct in json file. when serializing json, i'd serialize in own way, returning base58 string vec<u8> fields.

this own implementation:

impl serialize transactioncontent {     fn serialize<s>(&self, serializer: s) -> result<s::ok, s::error>         s: serializer     {         let mut state = serializer.serialize_struct("transactioncontent", 5)?;         state.serialize_field("sender_addr", &self.sender_addr.to_base58())?;         state.serialize_field("sender_pubkey", &self.sender_pubkey.to_base58())?;         state.serialize_field("receiver_addr", &self.receiver_addr.to_base58())?;         state.serialize_field("amount", &self.amount)?;         state.serialize_field("timestamp", &self.timestamp)?;         state.end()     } }

i can't use above code simultaneously. if use auto derive, second impl isn't possible. if use second one, bincode::serialize function work not want (i want use vec<u8> it)

is there way use both impl @ same time? conditional impl example?

no, cannot implement same trait multiple times in multiple ways single type.

as mentioned in comment, can create newtype wraps full data , implement required traits on that:

extern crate serde; extern crate serde_json; #[macro_use] extern crate serde_derive;  use serde::{serialize, serializer}; use serde::ser::serializestruct;  #[derive(debug, serialize)] struct real {     data: vec<u8>, }  struct asjson<'a>(&'a real);  impl<'a> serialize asjson<'a> {     fn serialize<s>(&self, serializer: s) -> result<s::ok, s::error>             s: serializer,     {         let mut state = serializer.serialize_struct("thing", 1)?;         state.serialize_field("data", b"this data")?;         state.end()     } }  fn main() {     let r = real { data: vec![1,2,3,4] };     println!("{:?}", serde_json::to_string(&r));     println!("{:?}", serde_json::to_string(&asjson(&r))); }

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