Tercioo@22: -- $Id: LibStub.lua 103 2014-10-16 03:02:50Z mikk $
Tercioo@22: -- LibStub is a simple versioning stub meant for use in Libraries.  http://www.wowace.com/addons/libstub/ for more info
Tercioo@22: -- LibStub is hereby placed in the Public Domain
Tercioo@22: -- Credits: Kaelten, Cladhaire, ckknight, Mikk, Ammo, Nevcairiel, joshborke
tercio@0: local LIBSTUB_MAJOR, LIBSTUB_MINOR = "LibStub", 2  -- NEVER MAKE THIS AN SVN REVISION! IT NEEDS TO BE USABLE IN ALL REPOS!
tercio@0: local LibStub = _G[LIBSTUB_MAJOR]
tercio@0: 
Tercioo@22: -- Check to see is this version of the stub is obsolete
tercio@0: if not LibStub or LibStub.minor < LIBSTUB_MINOR then
tercio@0: 	LibStub = LibStub or {libs = {}, minors = {} }
tercio@0: 	_G[LIBSTUB_MAJOR] = LibStub
tercio@0: 	LibStub.minor = LIBSTUB_MINOR
tercio@0: 	
Tercioo@22: 	-- LibStub:NewLibrary(major, minor)
Tercioo@22: 	-- major (string) - the major version of the library
Tercioo@22: 	-- minor (string or number ) - the minor version of the library
Tercioo@22: 	-- 
Tercioo@22: 	-- returns nil if a newer or same version of the lib is already present
Tercioo@22: 	-- returns empty library object or old library object if upgrade is needed
tercio@0: 	function LibStub:NewLibrary(major, minor)
tercio@0: 		assert(type(major) == "string", "Bad argument #2 to `NewLibrary' (string expected)")
tercio@0: 		minor = assert(tonumber(strmatch(minor, "%d+")), "Minor version must either be a number or contain a number.")
tercio@0: 		
tercio@0: 		local oldminor = self.minors[major]
tercio@0: 		if oldminor and oldminor >= minor then return nil end
tercio@0: 		self.minors[major], self.libs[major] = minor, self.libs[major] or {}
tercio@0: 		return self.libs[major], oldminor
tercio@0: 	end
tercio@0: 	
Tercioo@22: 	-- LibStub:GetLibrary(major, [silent])
Tercioo@22: 	-- major (string) - the major version of the library
Tercioo@22: 	-- silent (boolean) - if true, library is optional, silently return nil if its not found
Tercioo@22: 	--
Tercioo@22: 	-- throws an error if the library can not be found (except silent is set)
Tercioo@22: 	-- returns the library object if found
tercio@0: 	function LibStub:GetLibrary(major, silent)
tercio@0: 		if not self.libs[major] and not silent then
tercio@0: 			error(("Cannot find a library instance of %q."):format(tostring(major)), 2)
tercio@0: 		end
tercio@0: 		return self.libs[major], self.minors[major]
tercio@0: 	end
tercio@0: 	
Tercioo@22: 	-- LibStub:IterateLibraries()
Tercioo@22: 	-- 
Tercioo@22: 	-- Returns an iterator for the currently registered libraries
Tercioo@22: 	function LibStub:IterateLibraries() 
Tercioo@22: 		return pairs(self.libs) 
Tercioo@22: 	end
Tercioo@22: 	
tercio@0: 	setmetatable(LibStub, { __call = LibStub.GetLibrary })
tercio@0: end