rustHow to modify an existing entry in a Rust HashMap?

To modify an existing entry in a Rust HashMap, you can use the insert() method. This method takes two arguments, the key and the value, and replaces the existing value associated with the key with the new value.

Example code

use std::collections::HashMap;

let mut map = HashMap::new();
map.insert("key1", "value1");
map.insert("key1", "value2");

Output example

()

Code explanation

• use std::collections::HashMap;: imports the HashMap type from the standard library.
• let mut map = HashMap::new();: creates a new, empty HashMap.
• map.insert("key1", "value1");: inserts a new key-value pair into the HashMap.
• map.insert("key1", "value2");: replaces the existing value associated with the key "key1" with the new value "value2".

Helpful links

• Rust HashMap documentation

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