Pattern Matching

Basic Match

fn describe(n: int) -> string {
    return match n {
        0 => "zero"
        1 => "one"
        _ => "other"
    }
}

Guards

fn classify(n: int) -> string {
    return match n {
        0 => "zero"
        _ if n < 0 => "negative"
        _ if n > 100 => "big"
        _ => "normal"
    }
}

Match with Arrays

for i in [-1, 0, 1, 42, 200] {
    println("${i}: ${classify(i)}")
}

Output:

-1: negative
0: zero
1: normal
42: normal
200: big

Try It

🐉 Playground

fn classify(n: int) -> string { return match n { 0 => "zero" 1 => "one" _ if n < 0 => "negative" _ if n > 100 => "big" _ => "normal" } } for i in [-1, 0, 1, 42, 200] { println("${i}: ${classify(i)}") }

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