trackingTableAccess.lua

t = {}

--keep a private access to the original table

local _t = t

--create proxy
t = {}

--create metatable
local mt = {
  __index = function ( t, k )
		print("*access to element " .. tostring(k))
		return _t[k] --access the original table
	end,

	__newindex = function(t, k, v)
		print("update of element " .. tostring(k) ..
			" to " .. tostring(v))
		_t[k] = v --update original table
	end
}
setmetatable(t, mt)

t[2] = "hello"

print(t[2])