Lua classes and inheritance

[tjheldna]

Hi All,

 

I've been a big C++ guy from the start, but I want to learn how to use lua. Most I've found pretty straight forward however I'm trying to implement classes and inheritance and have hit a wall with inheritance.

 

What I'm trying to do is have an InventoryItem class and a GunItem which inherits. Maybe I'm a little off today, don't know, I just can't seem to understand from examples from the net and I don't know if they work in LE.

 

Does anyone know of a simple tutorial for this? or have an example handy?

 

Cheers!!!!

[Daimour]

There are tons of approaches to make inheritance in Lua.

 

First of all you need to decide - "do you really need inheritance?" Or you just need similar behave for group of objects?

 

In Lua you can override properties and methods of objects "on the fly". And you don't need "polymorphism" because Lua has no types in common and you don't have to deal with type-casting.

 

The easiest way (IMO) to create similar-behave objects - to make factory-functions for each type of objects.

 

function CreateInventoryItem(picture, weight)

local obj = {}

obj.picture = picture

obj.weight = weight

 

return obj

end

 

function CreateGunItem(picture, weight, damage)

local obj = CreateInventoryItem(picture, weight)

obj.damage = damage

 

return obj

end

[tjheldna]

That's easy, thanks Daimour! I'll try it soon.

[Admin]

You can assign functions to objects just like you can add members.