Rust: What is the difference between match and if let?

match — exhaustive pattern matching (all cases). if let — single pattern match.

match:

• Exhaustive — compiler checks all variants are handled.
• Supports guards, multiple patterns, destructuring.
• Returns a value from all branches.
• More verbose but more powerful.

1let value = Some(5);
2match value {
3    Some(x) if x > 10 => println!("Big: {}", x),
4    Some(x) => println!("Small: {}", x),
5    None => println!("Nothing"),
6}
7
8let result = match value {
9    Some(n) => n * 2,
10    None => 0,
11};

if let:

• Matches only one pattern — simpler.
• Good when you only care about one case.
• Can chain with else or else if let.
• Reduces boilerplate.

1if let Some(value) = value {
2    println!("Got: {}", value);
3} else {
4    println!("Nothing");
5}
6
7// Multiple patterns
8if let Some(x) = value {
9    println!("Got: {}", x);
10} else if let None = value {
11    println!("Nothing");
12}

When to use:

• Use match for complex multi-case pattern matching.
• Use if let when you only care about one pattern.
• Use if let for simpler fallback handling.

Common mistakes:

• Missing a variant in match — compiler error.
• Using if let when multiple cases need handling.
• Forgetting the else branch when needed.