function foo()
  local x, y = something(4, 5)
  return x ^ y
end

Multiple return values

-- Functions can return multiple values!
function something(arg1, arg2)
  local ret1 = (arg1 * arg2) ^ 2
  local ret2 = (arg1 - arg2) ^ 2
  return ret1 + ret2, ret1 * ret2
end

Also returns, function calls, and assignments all work with lists that can be mismatched in length. Any unmatched receivers are nil. Unmatched senders are discarded.

x, y, z = 1, 2, 3, 4

function bar(a, b, c)
  print(a, b, c)
  return 4, 8, 15, 16, 23, 42
end

x, y = bar('zaphod')  --> prints "zaphod  nil nil"
-- Now x = 4, y = 8, values 15...42 are discarded.

No parens

Bit silly, but there's a special case for functions which take a single string parameters. They do not need parentheses:

print 'hello world'