module main

type DataFn = fn (name string) string

fn which_lang(name string) string {
    return name
}

fn find_func(name string) ?DataFn {
    return match name {
        'vlang' { which_lang }
        else { none }
    }
}

fn test_main() {
    req := find_func('vlang')?
    fun := req('options')
    println(fun)
    assert fun == 'options'
}

fn test_ifguard() {
    if req2 := find_func('vlang') {
        assert req2('options') == 'options'
    }
}