How do you implement display formatting in Rust?

Question

Accepted Answer

**Display trait** — custom formatting.

**Implementation:**
```rust
use std::fmt;

struct Point {
    x: f64,
    y: f64,
}

impl fmt::Display for Point {
    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
        write!(f, "({}, {})", self.x, self.y)
    }
}

let p = Point { x: 1.0, y: 2.0 };
println!("{}", p);  // (1, 2)
```

**Debug trait:**
```rust
#[derive(Debug)]
struct Point { x: f64, y: f64 }

println!("{:?}", p);  // Point { x: 1.0, y: 2.0 }
println!("{:#?}", p);  // Pretty print
```

**Key:** Display for user output, Debug for debugging.

Rust: How do you implement display formatting in Rust?