into_inner_derive 0.1.2

Derive macro for IntoInner trait
Documentation 
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# into_inner_derive

[![Crates.io](https://img.shields.io/crates/v/into_inner_derive.svg)](https://crates.io/crates/into_inner_derive)
[![Docs.rs](https://docs.rs/into_inner_derive/badge.svg)](https://docs.rs/into_inner_derive)

Procedural macro for automatically implementing the `IntoInner` trait (from the [`into_inner`](https://crates.io/crates/into_inner) crate) for tuple structs with a single field.

---

## Overview

`into_inner_derive` provides the `#[derive(IntoInner)]` procedural macro, which generates an implementation of the `IntoInner` trait (from the [`into_inner`](https://crates.io/crates/into_inner) crate) for tuple structs with exactly one field. This allows you to easily extract the inner value from wrapper types without writing boilerplate code.

> **Note:**  
> You should **not** use this crate directly. Instead, use the macro re-exported by the main [`into_inner`](https://crates.io/crates/into_inner) crate:
>
> ```rust
> use into_inner::IntoInner;
>
> #[derive(IntoInner)]
> struct MyWrapper(String);
> ```

---

## Usage

Add the main crate to your `Cargo.toml`:

```toml
[dependencies]
into_inner = "0.1"
```

Then, in your code:

```rust
use into_inner::IntoInner;

#[derive(IntoInner)]
struct MyWrapper(String);

let wrapper = MyWrapper("Hello, world!".to_string());
let inner = wrapper.into_inner();
assert_eq!(inner, "Hello, world!");
```

---

## Limitations

- The macro **only** works for tuple structs with exactly one field.
- Using the macro on structs with named fields or multiple fields will result in a compile-time error.
- The `IntoInner` trait must be in scope when using the macro.

---

## Example: Compile-Time Error

```rust,compile_fail
use into_inner::IntoInner;

#[derive(IntoInner)]
struct InvalidWrapper(String, i32); // Error: only tuple structs with one field are supported
```

---

## License

Licensed under either of [Apache License, Version 2.0](LICENSE-APACHE) or [MIT license](LICENSE-MIT) at your option.

---

## Contribution

Contributions are welcome! Please open issues or pull requests on [GitLab](https://gitlab.com/max.martinelli/into_inner).

---

## See Also

- [into_inner](https://crates.io/crates/into_inner) — the main crate re-exporting the trait and macro.