Lua深复制，浅复制实现

table.copy = function(t)

local u = { }

for k, v in pairs(t) do u[k] = v end

return setmetatable(u, getmetatable(t))

end

table.deepCopy = function(t)

local function _deepCopy(from ,to)

for k, v in pairs(from) do

if type(v) ~= “table” then

to[k] = v;

else

to[k] = {};

_deepCopy(v,to[k]);

end

end

return setmetatable(from, getmetatable(to))

end

local u = {}

_deepCopy(t,u)

return u

end