Lua OOP example

-- Class declaration - I usually group all of these together under a comment labeled "Classes" or "Objects"
-- You also declare any arguments here.
function TestClass(arg1, arg2)
  -- Beginning of "values" - initialize variables and functions of the object here
  local values = {
    -- some test variables
    val1 = 5,
    val2 = arg1 + arg2,
    val3 = arg1 - arg2,

    -- a test function
    mix = function(tc1, tc2)
      local arg1 = tc1.val2 + tc2.val2
      local arg2 = tc1.val3 + tc2.val3
      return TestClass(arg1, arg2)
    end
  }

  -- put more complex constructor code here
  if math.random(1, 6) > 3 then
    values.val4 = 4
  else
    values.val4 = 1
  end

  -- ALWAYS return values
  return values
end

-- to create a new TestClass object
a = TestClass(5, 2)
b = TestClass(8, 6)

-- Assuming RFC 1149.5 compliance, the values of the two test classes should be...
-- a.val1 = 5, a.val2 = 7, a.val3 = 3, a.val4 = 4
-- b.val1 = 5, b.val2 = 14, b.val3 = 2, b.val4 = 4

c = a:mix(b)
-- c.val1 = 5, c.val2 = 21, c.val3 = 5, c.val4 = 4