UESP:ESO Lua File v100019 -- libraries/utility/baseobject.lua

ZO_Object = {}

function ZO_Object:New(template)

--

-- The new instance of the object needs an index table.

-- This next statement prefers to use "template" as the

-- index table, but will fall back to self.

-- Without the proper index table, your new object will

-- not have the proper behavior.

--

template = template or self

--

-- This call to setmetatable does 3 things:

-- 1. Makes a new table.

-- 2. Sets its metatable to the "index" table

-- 3. Returns that table.

--

local newObject = setmetatable ({}, template)

--

-- Obtain the metatable of the newly instantiated table.

-- Make sure that if the user attempts to access newObject[key]

-- and newObject[key] is nil, that it will actually fall

-- back to looking up template[key]...and so on, because template

-- should also have a metatable with the correct __index metamethod.

--

local mt = getmetatable (newObject)

mt.__index = template

return newObject

end

function ZO_Object:Subclass()

--

-- This is just a convenience function/semantic extension

-- so that objects which need to inherit from a base object

-- use a clearer function name to describe what they are doing.

--

return setmetatable({}, {__index = self})

end

function ZO_Object.MultiSubclass(...)

local parentClasses = {...}

return setmetatable({},

{

__index = function(table, key)

for _, parentClassTable in ipairs(parentClasses) do

local value = parentClassTable[key]

if value ~= nil then

return value

end

})

end

--[[

Here is a simple multiple inheritence example:

local A = ZO_Object:Subclass()

function A:InitializeA()

    self.name = "A"

end

local B = ZO_Object:Subclass()

function B:InitializeB()

    self.text = "B"

end

C = ZO_Object.MultiSubclass(A, B)

function C:New()

    local obj = ZO_Object.New(self)

    obj:Initialize()

    return obj

end

function C:Initialize()

    self:InitializeA()

    self:InitializeB()

end

]]

--