Unwrap and Expect

Quick error handling with unwrap and expect.

Difficulty

Beginner

Code

fn main() {
    // unwrap: panics with default message
    let home: std::net::IpAddr = "127.0.0.1".parse().unwrap();
    println!("{}", home);

    // expect: panics with custom message
    let port: u16 = "8080".parse().expect("port should be a number");
    println!("{}", port);

    // Option unwrap
    let x: Option<i32> = Some(5);
    let y: i32 = x.unwrap();
    println!("{}", y);
}

Explanation

unwrap() panics on None/Err. expect() adds custom message.

Key Concepts

• Read the code carefully and understand the data flow
• Try modifying the example to see how it changes behavior
• Run this code in the Rust Playground

Related Topics

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