/// This can be working with the latest version

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

let ps: Array<Point> = [
    Point(0, 0),
    Point(1, 2),
    Point(2, 3),
    Point { y = 3, x = 1, },
];

enum Z {
    Z1,  // Z is this,
    Z2,  // xor this.
}

// Blocks ({}) make a scope.
let your_name = {
    let first_name = "Hoge";
    let family_name = "Fuga";
    first_name + " " + family_name
};

// Of cource You can declar new struct and enum in {}.
let records = {
    struct UserRecord {
        id: Int,
        name: String = "Anonymous",  // set default value
        region: Region = Region::Unknown,
    }
    enum Region {
        Unknown,
        East,
        West,
    }
    // These struct and enum can be used only in this {scope}.
    [
        UserRecord(1, "Taro", Region::East),
        UserRecord { id = 2, name = "Alan", region = Region::West, },
        UserRecord { id = 3, name = "Bob" },
        UserRecord { id = 4, region = Region::East },
    ]
};

// Numbers
let z: Nat = 0;

// You can overwrite var names
let z = Z::Z2; // Enum Variant

// Option<_> types can represent "null-able" values.
let some_value: Option<String> = Some("Name");  // Not Null
let null_value: Option<String> = None;  // Null.

// Exporting this
{{
    env = {{
        shell = $SHELL,  // this is a String
        HOGE = ${HOGE:-fuga},  // with default value "fuga"
        NUM = ${NUM:-42} as Int,  // String -> Int cast
        BETA = ${BETA:-0.01} as Float,
    }},
    points = ps,
    z = z,
    user_name = your_name,
    records = records,

    options = {{
        some_value = some_value,
        null_value = null_value,
    }},

}}