/Tukui/modules/chat/telltarget.lua

local T, C, L = unpack(select(2, ...)) -- Import: T - functions, constants, variables; C - config; L - locales
if C["chat"].enable ~= true then return end

-- /tt - tell your current target.
for i = 1, NUM_CHAT_WINDOWS do
	local editBox = _G["ChatFrame"..i.."EditBox"]
	editBox:HookScript("OnTextChanged", function(self)
	   local text = self:GetText()
	   if text:len() < 5 then
		  if text:sub(1, 4) == "/tt " then
			 local unitname, realm
			 unitname, realm = UnitName("target")
			 if unitname then unitname = gsub(unitname, " ", "") end
			 if unitname and not UnitIsSameServer("player", "target") then
				unitname = unitname .. "-" .. gsub(realm, " ", "")
			 end
			 ChatFrame_SendTell((unitname or L.chat_invalidtarget), ChatFrame1)
		  end
	   end
	end)
end