rustHow to print the keys of a Rust HashMap?

You can print the keys of a Rust HashMap using the keys() method. This method returns an iterator over the keys of the HashMap.

Example code

use std::collections::HashMap;

let mut map = HashMap::new();
map.insert("a", 1);
map.insert("b", 2);

for key in map.keys() {
    println!("{}", key);
}

Output example

a
b

Code explanation

• use std::collections::HashMap: imports the HashMap type from the std::collections module.
• let mut map = HashMap::new(): creates a new empty HashMap and stores it in the map variable.
• map.insert("a", 1) and map.insert("b", 2): inserts two key-value pairs into the map HashMap.
• for key in map.keys(): iterates over the keys of the map HashMap.
• println!("{}", key): prints the current key.

Helpful links

• Rust HashMap documentation

Edit this code on GitHub