Oop And Meta Tables

What's the benefit of using Meta Tables with the Object Oriented aspect of lua?

For example,

Object Class

objectClass = {}
	objectClass.new = function(...)
	   newObject = {}
	   newObject.getVariable = function(self)
		   return self.variable
	   end
	   return newObject
   end
return objectClass

Main File

object = require('objectClass') -- The way I do it in love2d
myObject = object.new(...)
myObject:getVariable()
...etc

That's object oriented, and works fine.
I personally am not a big fan of metatables and try to avoid them wherever possible.

When you use metatables, you can make it "faster" because it's only creating the functions one time. And you can use the __call method ehich looks kinda cool :D/>

local BaseClass = {}
BaseClass.__index = BaseClass
BaseClass.__call = function(...)
  return BaseClass.new(...)
end
BaseClass.getType = function()
  return "BaseClass"
end
BaseClass.new = function()
  return setmetatable({},{__index=BaseClass})
end
setmetatable(BaseClass,BaseClass)

--# Usage example
local class = BaseClass()
print(class.getType())

Metatables are almost never necessary depending on what you're doing. They exist to essentially allow you to emulate different OO-related constructs commonly found in other languages. You're free to code without them if you want.

As freack100 attempted to state the major advantage of using metatables is being able to implement metamethods, meaning that you objects can respond to mathematical operators such as + - * / which are __add __sub __mul __div and all the other various metamethods we have available…

Also, metatables are useful for inheritance and storing hidden data.

However, you can do whatever you need without metatables, using normal tables and closures.