Closures in Rust

Snippet

Closures in Rust

Closures are anonymous functions that can capture their environment. They are defined with pipe syntax |x|. Unlike regular functions, closures can infer parameter types. Methods like fold() combine all elements using a closure, demonstrating functional programming patterns in Rust.

snippet.rs
rust
fn main() {
    let add = |x: i32, y: i32| -> i32 { x + y };
    let multiply = |x, y| x * y;
    println!("Add: {}", add(3, 4));
    println!("Multiply: {}", multiply(5, 6));
    
    let numbers = vec![1, 2, 3, 4, 5];
    let sum = numbers.iter().fold(0, |acc, x| acc + x);
    println!("Sum: {}", sum);
}

Breakdown

|x: i32, y: i32| -> i32 { x + y }

Closure with explicit parameter and return types

|x, y| x * y

Closure with inferred types (shorter syntax)

.fold(0, |acc, x| acc + x)

Reduces vector to single value by accumulating with closure

Previous snippet Next snippet

From your library

Closures in Rust

Related