function partial(fn, arg1)
  return function(...)
    return fn(arg1, ...)
  end
end

function add(n1, n2)
  return n1 + n2
end

function mul(n1, n2)
  return n1 * n2
end

local s5 = partial(add, 5)
print(s5(5))
assert(s5(5) == 10)

local doubler = partial(mul, 2)
print('32 * 2 =', doubler(32))
print('14 * 2 =', doubler(14))