Match value

# A `match` that gives a value (owner, 2026-09-29: a): a case whose block holds only a value is
# that value; a case may still leave instead (`return`, `fail`, `break`). The same holds for
# `otherwise` with several reasons. Every case is still covered.
enum Status { empty, claimed: str.utf8, locked }
fn label ['s': Status] -> str.utf8 {
    let 'text' := match 's' {
        empty         { is "free"; }
        claimed 'who' { is "taken by " ++ 'who'; }
        locked        { return "(locked)"; }
    };
    return give 'text';
}
MAIN {
    let 'n' := to.int32["12x"] otherwise { not_a_number { is -2; } out_of_range { is -1; } };
    std::print.useful[label[Status.empty], " / ", label[Status.claimed["ann"]], " / ", label[Status.locked], " / ", 'n', newln];
    match Status.empty {
        empty { std::print.useful["statement match still works", newln]; }
        claimed 'w' { }
        locked { }
    }
}