Why does RegisterUnitEvent responds to all units if the unit parameter is set to nil?

[Lyak]

How's everyone going?!

So, the title says pretty much all.

Why does RegisterUnitEvent responds to all units if the unit parameter is set to nil?

I currently have the following code.

if info.event then
    for event, unit in pairs(info.event) do
        if type(unit) == "table" then
            object:RegisterUnitEvent(event, unit[1], unit[2]);
        else
            object:RegisterEvent(event);
        end
    end
 
    object:SetScript("OnEvent", function(self, event, ...)
        prototype[event](self, info, ...);
    end);
end

This will make an object respond to all units if unit[2] is nil.

Why...?

I could just make an extra if statement to check if unit[2] exists, but before that I really want to know what's the difference between leaving the second unit parameter empty and assigning nil?

[myrroddin]

RegisterUnitEvent looks for unitIDs, which are strings. "player", "target", "boss1", "raid9", etc. What you are passing is a table, which means it probably has a fallback to a valid unitID, or string.

[Vrul]

As long as the table has at least one entry then this should work:

object:RegisterUnitEvent(event, unpack(unit))

[Lyak]

Originally Posted by myrroddin RegisterUnitEvent looks for unitIDs, which are strings. "player", "target", "boss1", "raid9", etc. What you are passing is a table, which means it probably has a fallback to a valid unitID, or string.

Hi myrroddin,

But the problem persist even if I try these

object:RegisterUnitEvent("UNIT_AURA", nil, "player");
-- or
object:RegisterUnitEvent("UNIT_AURA", "player", nil);

Originally Posted by Vrul As long as the table has at least one entry then this should work: object:RegisterUnitEvent(event, unpack(unit))

Ah! That's a great tip!

Thank you Vrul