In Rust, we can extract the keys and values from a HashMap using the iter() and keys() / get() / unwrap() functions.
Test Data
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let my_map:HashMap<i32, String> = HashMap::new(); my_map.insert(1, "one".to_string()); my_map.insert(2, "two".to_string()); my_map.insert(3, "three".to_string()); |
Using iter()
Note that iter() return all key-value pairs in arbitrary order.
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for (k, v) in my_map.iter() { println!("key={}, value={}", k, v); } |
Output 1
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key: 1 | value: one key: 3 | value: three key: 2 | value: two |
Output 2
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key: 2 | value: two key: 1 | value: one key: 3 | value: three |
Using keys()
Note that keys() also return keys in arbitrary order.
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for x in my_map.keys() { println!("{}", x); println!("{}", my_map.get(x).unwrap()); } |
Output 1
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1 one 3 three 2 two |
Output 2
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3 three 1 one 2 two |
