type Any = string | int

fn (m map[string]Any) to_toml() string {
    mut t := ''
    return t
}

fn test_main() {
    mut doc := map[string]Any{}
    _ := encode(doc)
}

fn encode[T](typ T) string {
    $for method in T.methods {
        $if method.name == 'to_toml' {
            return typ.$method()
        }
    }
    mp := encode_struct[T](typ)
    return mp.to_toml()
}

fn encode_struct[T](typ T) map[string]Any {
    mut mp := map[string]Any{}
    return mp
}