agila-learning-examples/en/vlang-practice-20261101/lesson-2/main.v

fn checked_score(value int) !int {
    if value < 0 || value > 100 { return error('Invalid score') }
    return value
}
fn main() {
    result := checked_score(101) or {
        println('Practice')
        return
    }
    println(result)
}