API Frame IsEventRegistered

Returns whether a frame is registered to an event.
 isRegistered, unit1, ... = Frame:IsEventRegistered(eventName)
==Arguments==
:;eventName: - Name of the frame event.
==Returns==
:;isRegistered: - True if the frame is registered for an event, false otherwise. Invalid event names always return false.
:;unit1, ...: : UnitId - Any registered units from .
==Example==
Prints if PLAYER_LOGIN is registered on UIParent.
local isRegistered = UIParent:IsEventRegistered("PLAYER_LOGIN")
print(isRegistered) -- true
Prints the units from Frame:RegisterUnitEvent.
local function OnEvent(self, event, ...)
	print(event, ...)
end
local f = CreateFrame("Frame")
f:RegisterUnitEvent("UNIT_HEALTH", "player", "party1", "party2", "party3")
f:SetScript("OnEvent", OnEvent)
print(f:IsEventRegistered("UNIT_HEALTH")) -- true, "player", "party1", "party2", "party3"
==Patch changes==
===References===