Macro dyn_clone::clone_trait_object

source ·
macro_rules! clone_trait_object {
    ($($path:tt)+) => { ... };
}
Expand description

Implement the standard library Clone for a trait object that has DynClone as a supertrait.

use dyn_clone::DynClone;

trait MyTrait: DynClone {
    /* ... */
}

dyn_clone::clone_trait_object!(MyTrait);

// Now data structures containing Box<dyn MyTrait> can derive Clone.
#[derive(Clone)]
struct Container {
    trait_object: Box<dyn MyTrait>,
}

The macro supports traits that have type parameters and/or where clauses.

use dyn_clone::DynClone;
use std::io::Read;

trait Difficult<R>: DynClone where R: Read {
    /* ... */
}

dyn_clone::clone_trait_object!(<R> Difficult<R> where R: Read);