jprjr_

  * pairs() returns next(), the table, 0. 
  * Lua calls next(table, 0) and next returns (1, some_value)
  * Lua calls next(table, 1) and next returns (2, another_value)
  * Lua calls next(table, 2) and next returns nil.

  local zpair_it = function(table, key)
    key = key + 1
    if table[key] then
      return key, table[key]
    end
  end

  local zpairs = function(table)
    return zpair_it, table, -1
  end

  local tab = { [0] = 'yay', [1] = 'huzzah' }
  for i,v in zpairs(tab) do
    print(i,v)
  end

  local dog_methods = {
    bark = function(self)
      print("bark bark I'm a",self.breed)
    end
  }

  local dog_metatable = {
    __index = dog_methods
  }

  local huskie = setmetatable({
    breed = 'huskie'
  }, dog_metatable)

  local collie = setmetatable({
    breed = 'collie'
  }, dog_metatable)

  huskie:bark()
  collie:bark()