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Example Programs

These examples show the current public surface of Metel as documented in the wiki.

Hello world​

fun main() {
    println("hello, Metel");
}

A small struct​

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

impl Point {
    fun magnitude(self) -> Float {
        return (self.x * self.x) + (self.y * self.y);
    }
}

fun main() {
    let p = Point { x: 3.0, y: 4.0 };
    println(p.magnitude());
}

Error handling with ?​

fun parse_and_double(input: String) -> Result<Int, String> {
    let value = parse_int(input)?;
    return Result::Ok { value: value * 2 };
}

Match and Perhaps​

fun describe(value: Perhaps<Int>) -> String {
    match value {
        Perhaps::Some { value } => "value: " + value.to_string(),
        Perhaps::None => "no value",
    }
}