trait_derive is a small crate that will generate a trait based on the impl blocks of your structs. This will save repitition in cases where you want to generate a trait for testing purposes, or you want to turn exsisting code into a trait for decoupling purposes.
To add it to your project, add the following line to your Cargo.toml
trait_derive = "0.1.0"
Currently, trait_derive requires you to be running nightly Rust. This will hopefully change in the future, once proc macros are stable.
Using this crate looks something like this:
#![feature(proc_macro)]
extern crate trait_derive;
use trait_derive::make_trait;
pub struct A;
#[make_trait] // This will generate a trait named 'TraitA' by default.
impl A {
pub fn hello_world(&self) {
println!("Hello, world!");
}
}
// Behind the scenes, we have generated code equivalent to
//trait TraitA {
// fn hello_world(&self);
//}
//
//impl TraitA for A {
// fn hello_world(&self) {
// println!("Hello, world!");
// }
//}
fn takes_trait(x: &TraitA) {
x.hello_world();
}
fn basic_usage() {
let a = A { };
takes_trait(&a);
}
#[make_trait(Database)] // This will generate a trait named 'Database'
impl A {
pub fn query(&self) -> u32 {
32
}
}