system.lua

local _G = _G

local super_t = {}
local super_mt = {
  __index = function(obj, field)
    local cls = class.super
    while(cls) do
      if cls.public[field] then return cls.public[field] end
      if cls.protected[field] then return cls.protected[field] end
      cls = cls.super
    end
    return nil
  end
}
setmetatable(super_t, super_mt)

local Object_mt = {
  __index = function(obj, field)
print(obj, field)
    local cls = obj.class
    local f
    if obj == _ENV and cls.private[field] then f = cls.private[field]
    else
      while cls do
        if cls.public[field] then
          f = cls.public[field]
          break
        elseif obj == _ENV and cls.protected[field] then
          f = cls.protected[field]
          break
        end
        cls = cls.super
      end
    end
print(f)
    if f == nil then return _G[field] end
print(f)
    if type(f) == "function" then
      return function(...)
        local olde = _ENV
print(_ENV)
print(obj)
        _ENV = obj
print(_ENV)
        local ret = f(...)
        _ENV = olde
        return ret
      end
    end
    return f
  end
}
local Object = {}

local classes = {}



function class(name)
  local super
  local function func(o)
    if type(o) == "string" then
      super = o
    elseif type(o) == "table" then
      classes[name] = o
      setmetatable(o, {__index = super and classes[super] or Object})
      o.public = o.public or {}
      o.private = o.private or {}
      o.protected = o.protected or {}
    end
    return func
  end
  return func
end
_G.class = class

function new(class)
  local cls = {}
  cls.class = classes[class] or Object
  cls.super = super_t
  cls._G = _G
  setmetatable(cls, Object_mt)
  return cls
end
_G.new = new