LibStub

LibStub
Library versioning tool
Details
TOC	n/a - meant to be embedded
Category	Libraries
Author	Kaelten et al.
Links
CurseForge

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LibStub is a minimalistic versioning library embedded by thousands of other addons. It allows addons to more easily share libraries by checking for the most recent version and making it available to other installed addons. This cross-community library-sharing system was creditted to Kaelten, Cladhaire, ckknight, Mikk, Ammo, Nevcairiel and joshborke; and has resided in the Public Domain since c. 2007.

LibStub-1.0 API

:GetLibrary(major [, silent])

Arguments

Arg	Type	Details
major	string	The name of the library you are requesting
silent	boolean	(Optional) Suppresses errors when the library is not found

Returns

Return	Type	Details
major	table or nil	The table instance of a registered library or nil if not found
minor	number	The minor revision of the registered library

:IterateLibraries()

Returns

An iterator over the registered major libraries.

:NewLibrary(major , minor)

Arguments

Arg	Type	Details
major	string	The name of the library you are requesting
minor	string or number	The minor for the registering library

Returns

Return	Type	Details
major	table or nil	The table to be used by the library.
oldminor	number	The minor revision of the previously registered library

Who uses LibStub?

• Ace3, for which it was originally designed

WoWAce.com Ace3

• Rock, ckknight's framework

WoWAce.com Rock

• Auctioneer uses it for its libraries

• Some Dongle-related libraries use it.

• ... and hopefully many more to come!

How to include LibStub in a library or addon

Library

• get a copy of the current version

• copy LibStub.lua into your library's folder

• set up your <library>.toc file to load LibStub.lua (in case you support stand alone loading of the lib)

• don't load LibStub via the xml file ment for embedded loading of your lib

• don't set LibStub as X-embeded or OptDep

AddOn

• set up an external pointing to svn://svn.wowace.com/wow/libstub/mainline/tags/1.0

or

• get a copy of the current version

• copy LibStub.lua into your addon's folder or a subfolder of it

• set up your <addon>.toc or embeds.xml file to load LibStub.lua

• don't set LibStub as X-embeded or OptDep

Examples

Basic usage

Using an integer for minor versions:

local lib = LibStub:NewLibrary("MyLibrary-1.0", 1)

if not lib then
	return  -- already loaded and no upgrade necessary
end

lib.somearray = lib.somearray or {}

if not lib.frame then
	lib.frame=CreateFrame("Frame")
end

function lib:SomeFunction()
	-- do stuff here
end

function lib:SomeOtherFunction()
	-- do other stuff here
end

local function OnUpdate()
	-- timing stuff here
end

lib.frame:SetScript("OnUpdate", OnUpdate);

Using revision control system tags for minor versions:

local lib = LibStub:NewLibrary("MyLibrary-1.0", "$Revision: 12345$")

if not lib then
	return  -- already loaded and no upgrade necessary
end

Bumping the number from a revision control system after it resets or slides backwards (i.e. when moving code from one repository to another):

local lib = LibStub:NewLibrary("MyLibrary-1.0", 
	12345+tonumber(strmatch("%d+","$Revision: 2$")) 
)

Embedding / Mixing in

This is a convention rather than a function of the specification, but all Ace3 and Rock related libraries use the following semantics for doing embedding / mixing in.

Specifically, libraries with an .Embed() member can be specified as embeds during addon object creation rather than having to embed them explicitly. At the end of the file, we handle library upgrades by re-embedding it in all positions where it was previously embedded / mixed in:

lib.mixinTargets = lib.mixinTargets or {}
local mixins = {"SomeFunction", "SomeOtherFunction" }

function lib:Embed(target)
	for _,name in pairs(mixins) do
		target[name] = lib[name]
	end
	lib.mixinTargets[target] = true
end



-- At the end of the file
for target,_ in pairs(mixinTargets) do
	lib:Embed(target)
end

External links

svn.WoWAce.com LibStub-1.0

www.WoWAce.com LibStub on wowace.com