rust macros traits

Derive macros for automatic trait implementations

Marcus Chen Jan 2026

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#[derive(Debug, Clone, PartialEq)]
struct Point {
    x: i32,
    y: i32,
}

fn main() {
    let p1 = Point { x: 1, y: 2 };
    let p2 = p1.clone();
    println!("{:?}", p1);
    assert_eq!(p1, p2);
}

1 file · rust Explain with highlit

Rust's #[derive] attribute auto-generates trait implementations for common traits like Debug, Clone, PartialEq, and Serialize. This eliminates boilerplate and ensures consistency. For example, #[derive(Debug)] generates a debug formatter that prints all fields. Custom derive macros (from crates like serde or thiserror) can generate complex code based on the struct definition. I derive Debug and Clone on almost every type during development. For production, I add Serialize and Deserialize for data that crosses boundaries. Derive macros are a form of compile-time metaprogramming that keeps code DRY without runtime cost. It's one of the features that makes Rust feel high-level despite being systems-focused.