ex-5.6.lua

-- Exercise 5.6: Write a function to test whether a given table is a
-- valid sequence.

function isseq (t)
   local len = 0
   for k, v in pairs(t) do
      if math.type (k) == "integer"
	 and k > 0 then
	 len = math.max (len, k)
      end
   end
   for i = 1, len do
      if t[i] == nil then
	 return false
      end
   end
   return true
end