Check If A Key Exists In A Rust BTreeMap

use std::collections::BTreeMap;

fn main() {
  let mut items: BTreeMap<String, String> = BTreeMap::new();
  items.insert("alfa".to_string(), "this is alfa".to_string());

  // Example when it key exists
  match items.get("alfa") {
    Some(value) => println!("Got: {}", value),
    None => println!("don't have it")
  }

  // Example when it key does not exists
  match items.get("bravo") {
    Some(value) => println!("Got: {}", value),
    None => println!("don't have it")
  }

}