easy-ext 0.1.0

# easy-ext

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[![documentation](https://docs.rs/easy-ext/badge.svg)](https://docs.rs/easy-ext/)
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[![Rustc Version](https://img.shields.io/badge/rustc-1.31+-lightgray.svg)](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 version of easy-ext requires Rust 1.31 or later.

## Examples

```rust
use easy_ext::ext;

#[ext(StrExt)]
impl str {
    fn foo(&self) -> String {
        /* */
    }
}
```

Code like this will be generated:

```rust
trait StrExt {
    fn foo(&self) -> String;
}

impl StrExt for str {
    fn foo(&self) -> String {
        /* */
    }
}
```

### 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)

### Visibility

* The generated extension trait inherits the visibility of the item in the original `impl`.

* The visibility of all the items in the original `impl` must be identical.

See [the test codes](tests/test.rs) for more examples.

## 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.