function test_1() = (3 = 3; () )

function test_2() =
  let
    var i := 1
    var j := 1
  in
    j := j + 1;
    i := i * j
  end

function test_3() =
  let
    var i := 1
    var j := 1
  in
    j := j - 1;
    i := i / j
  end