data List (a) where {
    Nil : List (a)
    Cons : a -> List (a) -> List (a)
};

-- data Bool () where {
--     True : Bool ()
--     False : Bool ()
--    };

-- hello_world = Cons 'h' (Cons 'e' (Cons 'l' (Cons 'l' (Cons 'o' (Cons ' ' (Cons 'w' (Cons 'o' (Cons 'r' (Cons 'l' (Cons 'd' Nil)))))))))) ;

-- length : List (a) -> Int ;
-- length xs = case xs of {
--     Nil => 0;
--     Cons x xs => length xs;
-- };

-- head : List (a) -> a ;
-- head xs = case xs of {
--     Cons x xs => x;
-- };

-- firstIsOne : List (Int) -> Bool () ;
-- firstIsOne xs = case xs of {
--     Cons x xs => case x of {
--             0 => True;
--             _ => case xs of {
--                     Cons x xs => False;
--                     _ => False;
--                 };
--             };
--     _ => False;
--     };

-- main = firstIsOne (Cons 1 Nil);

test xs = case xs of {
    1 => 0;
    lol => 1;
                     };