Module:Class

local middleclass = { _VERSION    = 'middleclass v4.1.1', _DESCRIPTION = 'Object Orientation for Lua', _URL        = 'https://github.com/kikito/middleclass', _LICENSE    = [[    MIT LICENSE

Copyright (c) 2011 Enrique García Cota

Permission is hereby granted, free of charge, to any person obtaining a   copy of this software and associated documentation files (the    "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to   permit persons to whom the Software is furnished to do so, subject to    the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF   MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. ]] }

local function _createIndexWrapper(aClass, f) if f == nil then return aClass.__instanceDict else return function(self, name) local value = aClass.__instanceDict[name]

if value ~= nil then return value elseif type(f) == "function" then return (f(self, name)) else return f[name] end end end end

local function _propagateInstanceMethod(aClass, name, f) f = name == "__index" and _createIndexWrapper(aClass, f) or f  aClass.__instanceDict[name] = f

for subclass in pairs(aClass.subclasses) do   if rawget(subclass.__declaredMethods, name) == nil then _propagateInstanceMethod(subclass, name, f)   end end end

local function _declareInstanceMethod(aClass, name, f) aClass.__declaredMethods[name] = f

if f == nil and aClass.super then f = aClass.super.__instanceDict[name] end

_propagateInstanceMethod(aClass, name, f) end

local function _tostring(self) return "class " .. self.name end local function _call(self, ...) return self:new(...) end

local function _createClass(name, super) local dict = {} dict.__index = dict

local aClass = { name = name, super = super, static = {}, __instanceDict = dict, __declaredMethods = {}, subclasses = setmetatable({}, {__mode='k'}) }

if super then setmetatable(aClass.static, {     __index = function(_,k)        local result = rawget(dict,k)        if result == nil then          return super.static[k]        end        return result      end    }) else setmetatable(aClass.static, { __index = function(_,k) return rawget(dict,k) end }) end

setmetatable(aClass, { __index = aClass.static, __tostring = _tostring,                        __call = _call, __newindex = _declareInstanceMethod })

return aClass end

local function _includeMixin(aClass, mixin) assert(type(mixin) == 'table', "mixin must be a table")

for name,method in pairs(mixin) do   if name ~= "included" and name ~= "static" then aClass[name] = method end end

for name,method in pairs(mixin.static or {}) do   aClass.static[name] = method end

if type(mixin.included)=="function" then mixin:included(aClass) end return aClass end

local DefaultMixin = { __tostring  = function(self) return "instance of " .. tostring(self.class) end,

initialize  = function(self, ...) end,

isInstanceOf = function(self, aClass) return type(aClass) == 'table' and type(self) == 'table' and (self.class == aClass           or type(self.class) == 'table'            and type(self.class.isSubclassOf) == 'function'            and self.class:isSubclassOf(aClass)) end,

static = { allocate = function(self) assert(type(self) == 'table', "Make sure that you are using 'Class:allocate' instead of 'Class.allocate'") return setmetatable({ class = self }, self.__instanceDict) end,

new = function(self, ...) assert(type(self) == 'table', "Make sure that you are using 'Class:new' instead of 'Class.new'") local instance = self:allocate instance:initialize(...) return instance end,

subclass = function(self, name) assert(type(self) == 'table', "Make sure that you are using 'Class:subclass' instead of 'Class.subclass'") assert(type(name) == "string", "You must provide a name(string) for your class")

local subclass = _createClass(name, self)

for methodName, f in pairs(self.__instanceDict) do       _propagateInstanceMethod(subclass, methodName, f)      end subclass.initialize = function(instance, ...) return self.initialize(instance, ...) end

self.subclasses[subclass] = true self:subclassed(subclass)

return subclass end,

subclassed = function(self, other) end,

isSubclassOf = function(self, other) return type(other)     == 'table' and type(self.super) == 'table' and ( self.super == other or self.super:isSubclassOf(other) ) end,

include = function(self, ...) assert(type(self) == 'table', "Make sure you that you are using 'Class:include' instead of 'Class.include'") for _,mixin in ipairs({...}) do _includeMixin(self, mixin) end return self end } }

function middleclass.class(name, super) assert(type(name) == 'string', "A name (string) is needed for the new class") return super and super:subclass(name) or _includeMixin(_createClass(name), DefaultMixin) end

setmetatable(middleclass, { __call = function(_, ...) return middleclass.class(...) end })

return middleclass