1 // Copyright 2015 The Rust Project Developers. See the COPYRIGHT
2 // file at the top-level directory of this distribution and at
3 // http://rust-lang.org/COPYRIGHT.
5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
8 // option. This file may not be copied, modified, or distributed
9 // except according to those terms.
12 #![feature(rustc_private)]
14 extern crate serialize;
16 use serialize::{Encodable, Decodable};
17 use std::fmt::Display;
19 pub trait Entity : Decodable + Encodable + Sized {
20 type Key: Clone + Decodable + Encodable + ToString + Display + Eq + Ord + Sized;
22 fn id(&self) -> Self::Key;
24 fn find_by_id(id: Self::Key) -> Option<Self>;
27 pub struct DbRef<E: Entity> {
31 impl<E> DbRef<E> where E: Entity {
32 fn get(self) -> Option<E> {
33 E::find_by_id(self.id)