// Tuple types: (T, U), return, field access via .0 / .1
import Std::Io::{PrintLine, PrintInt};
import Std::Test::{Test_AssertEqInt, Test_Pass};

func MakePair(a: int, b: int) -> (int, int) {
    return (a, b);
}

func Swap(t: (int, int)) -> (int, int) {
    return (t.1, t.0);
}

func Main() -> int {
    let t: (int, int) = MakePair(10, 20);
    Test_AssertEqInt(t.0, 10);
    Test_AssertEqInt(t.1, 20);

    let s: (int, int) = Swap(t);
    Test_AssertEqInt(s.0, 20);
    Test_AssertEqInt(s.1, 10);

    let lit: (int, int) = (7, 8);
    Test_AssertEqInt(lit.0, 7);
    Test_AssertEqInt(lit.1, 8);

    PrintInt(t.0);
    PrintLine("");
    PrintInt(t.1);
    PrintLine("");
    Test_Pass("tuples");
    return 0;
}