rustHow to set the lifetime of a Rust HashMap?

The lifetime of a Rust HashMap can be set by using the HashMap::with_capacity_and_hasher method. This method takes two parameters, the capacity and the hasher. The capacity is the maximum number of elements the HashMap can hold, and the hasher is a type that implements the BuildHasher trait.

Example code

use std::collections::HashMap;
use std::hash::BuildHasher;

let mut map: HashMap<i32, i32> = HashMap::with_capacity_and_hasher(10, BuildHasher::default());

The code above creates a HashMap with a capacity of 10 and a default hasher.

Code explanation

• HashMap::with_capacity_and_hasher: This is the method used to set the lifetime of a Rust HashMap. It takes two parameters, the capacity and the hasher.
• capacity: This is the maximum number of elements the HashMap can hold.
• hasher: This is a type that implements the BuildHasher trait.

List of ## Helpful links

• Rust Documentation - HashMap

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