-- let A (x,y) be A(5,6) in write(x); write(y) ni;
-- case A(5,6) of A(x,y) -> write(x); write(y) esac;
-- let A (x,y) be A(5,6) in ....
-- let A (x,y) be A(5,6)    <-----  void then ;

fun f (x) {
    write(x)
}

f(let x = A(1,2) in x[0]);
f(let x = A(1,2) in x[1]);

let A (x,y) = A(5,6) in let B(z,e) = B(7,8) in write(x); write(y); write(z); write(e);
let A (x,y) = A(5,6) in (let B(z,e) = B(7,8) in write(x); write(y); write(z); write(e));

let x = (let x = C(1,2) in x[1]) + (let x = C(1,2) in x[0]) in write(x)