Check if key exists in HashMap - if the HashMap contains the key

If you'd like to know if a given key exists in a given HashMap you can use the contains_key method that will return a bool, that's either True of False.

examples/hashmap/check-if-key-exists/src/main.rs

use std::collections::HashMap;

fn main() {
    let mut animal = HashMap::new();


    animal.insert(String::from("snake"), String::from("long"));
    animal.insert(String::from("giraffe"), String::from("tall"));
    animal.insert(String::from("elephant"), String::from("heavy"));

    println!("{:#?}", animal);
    for name in ["turle", "snake"] {
        if animal.contains_key(name) {
            println!("{name} is in the HashMap and it is {}", animal[name]);
        } else {
            println!("{name} is NOT in the HashMap");
        }
    }
}