% Attributes

<small>There is a new edition of the book and this is an old link.</small>

> Any item declaration may have an attribute applied to it.

```rust
// A function marked as a unit test
#[test]
fn test_foo() {
    /* ... */
}
```

---

Here are the relevant sections in the new and old books:

* **[In the Rust Reference: Ch 6.5 — Attributes][2]**
* <small>[In the first edition: Ch 3.27 — Attributes][1]</small>


[1]: https://doc.rust-lang.org/1.30.0/book/first-edition/attributes.html
[2]: ../reference/attributes.html