The match statement in Rust is a powerful control flow operator that allows you to compare a value against a series of patterns and execute code based on which pattern matches. It's similar to switch statements in other languages but more powerful.

Basic Syntax

match value {
    pattern1 => expression1,
    pattern2 => expression2,
    _ => default_expression,
}

Key Features

• Exhaustive: Match must cover all possible cases
• Pattern Matching: Supports complex pattern matching including destructuring
• Type Safety: Ensures type-safe comparisons at compile time

Examples with Different Types

1. Basic Numbers

let number = 13;
match number {
    1 => println!("One"),
    2 | 3 | 5 | 7 | 11 | 13 => println!("This is a prime"),
    _ => println!("Not a prime"),
}

2. Tuples

let point = (0, 0);
match point {
    (0, 0) => println!("Origin"),
    (0, y) => println!("Y axis, y = {}", y),
    (x, 0) => println!("X axis, x = {}", x),
    (x, y) => println!("Point: ({}, {})", x, y),
}

3. Arrays and Slices

let arr = &[1, 2, 3];
match arr {
    &[] => println!("Empty array"),
    &[x] => println!("Single element: {}", x),
    &[x, y] => println!("Two elements: {} {}", x, y),
    &[x, .., z] => println!("Array with first {} and last {}", x, z),
}

4. Enums

enum Message {
    Quit,
    Move { x: i32, y: i32 },
    Write(String),
}

let msg = Message::Move { x: 3, y: 4 };
match msg {
    Message::Quit => println!("Quit"),
    Message::Move { x, y } => println!("Move to ({}, {})", x, y),
    Message::Write(text) => println!("Text message: {}", text),
}

5. Pointers and References

let reference = &4;
match reference {
    &val => println!("Got a value: {}", val),
}

// Reference matching with dereferencing
match *reference {
    val => println!("Got a value: {}", val),
}

6. Structs

struct Point {
    x: i32,
    y: i32,
}

let point = Point { x: 0, y: 7 };
match point {
    Point { x: 0, y } => println!("On y axis: {}", y),
    Point { x, y: 0 } => println!("On x axis: {}", x),
    Point { x, y } => println!("Point: ({}, {})", x, y),
}