Minimal class approach for Lua based on Tjakka5 code https://github.com/tjakka5/Babble/blob/master/babble/src/class.lua

miniclass.lua

local function new (self, ...)
   local obj = setmetatable({}, self)
   if self.initialize then self.initialize(obj, ...) end
   return obj
end

local mt = { __call = function (self, ...)
  return self:new(...)
end }

return function(name)
  local class = {name  = name, new   = new}

  class.class = class
  class.__index = class
  return setmetatable(class, mt)
end

Usage:

local class = require 'miniclass'

local MyClass = class('My Class')

function MyClass:initialize ()
   self.id = 0
end

function MyClass:setID (id)
  self.id = id
end


local Instance = MyClass:new()
Instance:setID(3)