LoadAddOn

Request the loading of an On-Demand AddOn.

loaded, reason = LoadAddOn(index or "name")

Parameters

Arguments

(index or "name")

index: Integer - The index of the AddOn in the user's AddOn list. Note that you cannot access Blizzard-provided AddOns through this mechanism.
name: String - The name of the AddOn to be queries. You can access Blizzard-provided AddOns through this mechanism.

Returns

loaded, reason

loaded: Flag - Indicates if the AddOn was loaded, 1 if it is, nil if it is not.
reason: String - The reason why the AddOn cannot be loaded. This is nil if the addon was loaded, otherwise it contains a code indicating the reason.

Usage

local loaded, reason = LoadAddOn("MyOtherAddOn")

if (not loaded) then
  if (reason == "DISABLED") then
   -- do stuff
  elseif (reason == "MISSING") then
   -- do other stuff
  elseif (reason == "CORRUPT") then
   -- do something else
  elseif (reason == "INTERFACE_VERSION") then
   -- do something different
  end
else
  -- do something special
end

Details

Prior to the 1.8 patch, this could be used to load addons which were not on-demand if they were disabled at start up and then enabled during the play session. The 1.8 patch restricted this to ONLY addons which are truly marked on demand in their .toc files (## LoadOnDemand: 1).

Reason Codes

(taken from FrameXML\GlobalStrings.lua)
(they are all prefixed with "ADDON_", use getglobal("ADDON_"..reason) for localizing)

BANNED: "Banned"; -- Addon is banned by the client.
CORRUPT: "Corrupt"; -- The addon's file(s) are corrupt.
DEP_BANNED: "Dependency banned"; -- Addon's dependency is banned by the client.
DEP_CORRUPT: "Dependency corrupt"; -- The addon's dependency cannot load because its file(s) are corrupt.
DEP_DISABLED: "Dependency disabled"; -- The addon cannot load without its dependency enabled.
DEP_INCOMPATIBLE: "Dependency incompatible"; -- The addon cannot load if its dependency cannot load.
DEP_MISSING: "Dependency missing"; -- The addon's dependency is physically not there.
DEP_NOT_DEMAND_LOADED: "Dependency not loadable on demand"; -- The addon's dependency must be loadable on demand too.
DISABLED: "Disabled"; -- Addon is disabled on the character select screen.
INCOMPATIBLE: "Incompatible"; -- The addon is too old.
MISSING: "Missing"; -- The addon is physically not there.
NOT_DEMAND_LOADED: "Not loadable on demand"; -- As of 1.8 only addons marked as LoadOnDemand can be loaded via this function.

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