ECS/object.lua

--[[
    Object base class
    @author : Siapran Candoris
    Features instance of class determination and prototype function (init)
]]--

local make_class = require("class")
--------------------------------
-- object class
--
local object = make_class()

function object:new( ... )
	local res = {}
	setmetatable(res, self)
	if res.init then
		res:init(...)
	end
	return res
end

function object:instanceof( class )
	local cache = self.__instanceof_cache
	if cache[class] ~= nil then
		return cache[class]
	else
		for _,v in ipairs(self.__genealogy) do
			if class == v then
				cache[class] = true
				return true
			end
		end
		cache[class] = false
		return false
	end
end

-- general purpose utils

-- asssign unique ids to tables
do
    local cache = setmetatable({}, {__mode = "k"})
    local id = 0
    function identifier( table )
        if cache[table] then
            return cache[table]
        else
            cache[table] = id
            id = id + 1
            return id
        end
    end
end

return object