Lua hax #84721365: Calling plain tostring in custom tostring metamethod to get table address.

main.lua

local t = {}

local toString = function(t)
	local original = getmetatable(t)
	local modified = {}; for k,v in pairs(original) do modified[k] = v end; modified.__tostring = nil
	setmetatable(t, modified)
	local address = tostring(t):sub(8)
	setmetatable(t, original)
	return string.format("Identifying table:\n%s\nYep, it's a table.", address)
end

setmetatable(t,{__tostring = toString})

print(t)