1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
|
[![Latest Version]][crates.io] [![Documentation]][docs.rs] [![GHA Status]][GitHub Actions] ![License]
Utilities for working with `impl Trait`s in Rust.
## `trait_variant`
`trait_variant` generates a specialized version of a base trait that uses `async fn` and/or `-> impl Trait`.
For example, if you want a [`Send`][rust-std-send]able version of your trait, you'd write:
```rust
#[trait_variant::make(IntFactory: Send)]
trait LocalIntFactory {
async fn make(&self) -> i32;
fn stream(&self) -> impl Iterator<Item = i32>;
fn call(&self) -> u32;
}
```
The `trait_variant::make` would generate an additional trait called `IntFactory`:
```rust
use core::future::Future;
trait IntFactory: Send {
fn make(&self) -> impl Future<Output = i32> + Send;
fn stream(&self) -> impl Iterator<Item = i32> + Send;
fn call(&self) -> u32;
}
```
Implementers can choose to implement either `LocalIntFactory` or `IntFactory` as appropriate.
For more details, see the docs for [`trait_variant::make`].
[`trait_variant::make`]: https://docs.rs/trait-variant/latest/trait_variant/attr.make.html
#### License and usage notes
Licensed under either of [Apache License, Version 2.0](LICENSE-APACHE) or
[MIT license](LICENSE-MIT) at your option.
[GitHub Actions]: https://github.com/rust-lang/impl-trait-utils/actions
[GHA Status]: https://github.com/rust-lang/impl-trait-utils/actions/workflows/rust.yml/badge.svg
[crates.io]: https://crates.io/crates/trait-variant
[Latest Version]: https://img.shields.io/crates/v/trait-variant.svg
[Documentation]: https://img.shields.io/docsrs/trait-variant
[docs.rs]: https://docs.rs/trait-variant
[License]: https://img.shields.io/crates/l/trait-variant.svg
[rust-std-send]: https://doc.rust-lang.org/std/marker/trait.Send.html
|
