lua_oop

implementation lua oop like in cpp

lua oop api

create class object
class.new(name)

• name : class name

local a = class.new("a")

create contructor of class
function obj:__init(...)

• obj : object of class
• ... : parameters of object contructor

function a:__init(...)
end

create destructor of class
function obj:__destroy()

• obj: object of class
• no parameters

function a:__destroy()
end

create function of class
function obj:func(...)

• function created as public function
• obj : object of class
• func : name of function
• ... : parameters of object function

function a:start(...)
end

function a:next(...)
end

set function attributes

• available attributes:

• • virtual = true

    function is virtual

  • access = class.PUBLIC

    function access, may be class.PUBLIC, class.PROTECTED, class.PRIVATE
    after setting function access
    function can be not available from global area(for access type PROTECTED and PRIVATE)

a.start.virtual = true
a.start.access = class.PROTECTED

create public attribute of object

a.data = 5

create protected or private attribute of object

• available only in class function, contructor or destructor

function a:__init(...)
  self.__private.pv_data = 6
  self.__protected.pt_data = 7
end

access to object attributes and functions

• public attributes and functions available from anywhere
• private attributes and functions available from owner class
• protected attributes and functions available from owner and inheritence class

print(a.data)      -- 5
print(a.pv_data)   -- nil
print(a.pt_data)   -- nil
function a:start()
  print(a.data)    -- 5
  print(a.pv_data) -- 6
  print(a.pt_data) -- 7
end
a:next()           -- not error: call successful
a:start()          -- error: attempts call nil value

inheriting classes
class.inherit(name, obj[, obj...])

• name : name of new class
• obj : parent class object

local b = class.new("b")
local c = class.inherit("c", a, b)

call function from parent class
super keyword
self.super:func(...)
self.super(name):func(...)
self.super.attr
self.super(name).attr

• super keyword return access to parent attributes and functions
• • func : function name
  • name : name of parent object
  • attr : name of parent object attribute

function c:start(...)
  self.data = 8              -- created data attribute of `c`
  print(self.data)  -- 8
  print(self.super(a).data)  -- 5
  print(self.super.pt_data)  -- 7
  print(self.super.pv_data)  -- nil
  return self.super:start()  -- not error: call successful
end

call virtual function

function a:virt()
  print("a:virt")
end
a.virt.virtual = true

function  c:virt()
  print("c:virt")
  self.super:virt()
end
a:virt()            -- c:virt
                    -- a:virt

call constructors

c({data=6})          -- calls a:__init(), b:__init() and c:__init()
a({data=6})          -- call only a:__init()
b({data=6})          -- call only b:__init()

destroy class object class.destroy(obj)

• function destroys all classes of object
  if __destroy() function is virtual is called all classes function from child to parent
  if __destroy() function is non virtual is called function of classes of from obj to its parent
• • obj : class object

    local a = class.new("a")
    local b = class.inherit("b", a)

    function a:__destroy()
      print("a:__destroy")
    end
    a.__destroy.virtual = true

    function b:__destroy()
      print("b:__destroy")
    end

    class.delete(a)   -- b:__destroy
                      -- a:__destroy