If Let

Concise pattern matching for a single case.

Difficulty

Beginner

Code

fn main() {
    let config_max: Option<u8> = Some(3);
    if let Some(max) = config_max {
        println!("max is {}", max);
    }

    let val: Result<i32, &str> = Ok(42);
    if let Ok(v) = val {
        println!("value: {}", v);
    }
}

Explanation

This example demonstrates how to use if let in Rust. Read the code carefully to understand the flow. Pay attention to where values are created, borrowed, moved, or consumed.

Key Concepts

• Rust's strong type system catches errors at compile time
• Ownership and borrowing rules ensure memory safety
• Pattern matching makes code expressive and exhaustive

Related Topics

Browse more examples in the flow-control category to build a complete understanding of this topic.