easy-ext 0.1.5

# easy-ext

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[azure-url]: https://dev.azure.com/taiki-e/taiki-e/_build/latest?definitionId=6&branchName=master
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[docs-url]: https://docs.rs/easy-ext/
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[rustc-url]: https://blog.rust-lang.org/2018/12/06/Rust-1.31-and-rust-2018.html

An attribute macro for easily writing [extension trait pattern](https://github.com/rust-lang/rfcs/blob/master/text/0445-extension-trait-conventions.md).

[**Documentation**](https://docs.rs/easy-ext/)

## Usage

Add this to your `Cargo.toml`:

```toml
[dependencies]
easy-ext = "0.1"
```

The current easy-ext requires Rust 1.31 or later.

## Examples

```rust
use easy_ext::ext;

#[ext(ResultExt)]
impl<T, E> Result<T, E> {
    fn err_into<U>(self) -> Result<T, U>
    where
        E: Into<U>,
    {
        self.map_err(Into::into)
    }
}
```

Code like this will be generated:

```rust
trait ResultExt<T, E> {
    fn err_into<U>(self) -> Result<T, U>
    where
        E: Into<U>;
}

impl<T, E> ResultExt<T, E> for Result<T, E> {
    fn err_into<U>(self) -> Result<T, U>
    where
        E: Into<U>,
    {
        self.map_err(Into::into)
    }
}
```

### Supported items

* [Methods](https://doc.rust-lang.org/book/ch05-03-method-syntax.html)

* [Associated constants](https://rust-lang-nursery.github.io/edition-guide/rust-2018/trait-system/associated-constants.html)

## License

Licensed under either of

* Apache License, Version 2.0, ([LICENSE-APACHE](LICENSE-APACHE) or <http://www.apache.org/licenses/LICENSE-2.0>)
* MIT license ([LICENSE-MIT](LICENSE-MIT) or <http://opensource.org/licenses/MIT>)

at your option.

### Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.