class.lua

To use this class implementation, it's extremely simple.

1. Build your class prototype in a regular lua table (optionally put a constructor in [prototype]:new).
2. Call class with your prototype as the first argument (and optionally a super class to extend as the second).

The resulting table is your class. You can call the :new method on it to create a new instance of it.

Example:

-- group.lua
local class = require "class"

local prototype = {}

function prototype:add(obj)
	table.insert(self, obj)
end

function prototype:remove(obj)
	for index, child in ipairs(self) do
		if child == obj then
			table.remove(self, index)
			return
		end
	end
end

return class(prototype)

-- main.lua
local Group = require "group"

local entities = Group:new()

Additional notes:

• class creates a metatable with a prefilled __index value under the hood. This means that after turning your prototype into a class, you can assign metamethods to it as you would normally.
• If a super class is specified, it will modify the prototype to assign a property named super containing the prototype of the extended class, as well as setting an __index metamethod on the prototype.