rust closeure

Rust Closures

In Rust, closures are anonymous functions that can capture variables from their surrounding environment. They are similar to functions but have some additional capabilities. Closures are defined using the |args| body syntax, where args are the arguments the closure takes and body is the code that gets executed when the closure is called.

Here's an example of a closure in Rust:

let add = |a, b| a + b;
let result = add(2, 3);
println!("Result: {}", result);

In this example, the closure add takes two arguments a and b and returns their sum. The closure is then called with the arguments 2 and 3, and the result is printed.

Closures can also capture variables from their surrounding environment. For example:

fn create_adder(a: i32) -> Box<dyn Fn(i32) -> i32> {
    Box::new(move |b| a + b)
}

let add_five = create_adder(5);
let result = add_five(3);
println!("Result: {}", result);

In this example, the create_adder function returns a closure that captures the variable a from its surrounding environment. The closure takes an argument b and returns the sum of a and b. The closure is then called with the argument 3, and the result is printed.

Closures in Rust have a unique type that implements one of the Fn, FnMut, or FnOnce traits, depending on how they capture variables and how they are used. This allows closures to be used in a flexible and efficient manner.

Note: The examples provided here are for illustrative purposes and may not cover all possible use cases or syntax variations. For more detailed information on closures in Rust, you can refer to the official Rust documentation or other reliable sources.