count matches with regex

To count matches with a regular expression in Rust, you can use the regex crate. Here's an example:

use regex::Regex;

fn main() {
    let re = Regex::new(r"pattern").unwrap();
    let text =```rust
use regex::Regex;

fn main() {
    let re = Regex::new(r"pattern").unwrap();
    let text = "example pattern example pattern";
    let count = re.find_iter(text).count();
    println!("{}", count);
}