I don't know about ace3's print, if it even exists... but there's always Spew if you like ace2's print but don't want to load all that shit just to get it.
Ace3's print here is actually referring to the
command that comes with the AceConsole-3.0 mixin. The code looks like this:
-- AceConsole:Print( [chatframe,] ... )
-- Print to DEFAULT_CHAT_FRAME or given chatframe (anything with an .AddMessage member)
local text = ""
if self ~= AceConsole then
text = "|cff33ff99"..tostring( self ).."|r: "
local frame = select(1, ...)
if not ( type(frame) == "table" and frame.AddMessage ) then -- Is first argument something with an .AddMessage member?
for i=(frame and 2 or 1), select("#", ...) do
text = text .. tostring( select( i, ...) ) .." "
(frame or DEFAULT_CHAT_FRAME):AddMessage( text )