SUB[test] StringLen
    "ASCII strlen"
    x = "foobar"
    assert LEN(x) == 6

    "Unicode strlen"
    x = "한글"
    assert LEN(x) == 2
end

SUB[test] ListLen
    assert LEN([]) == 0

    x = [1, 2, 3]
    assert LEN(x) == 3
end