tolua++: passing C++ objects to Lua?

[Enrico Colombini <erix@...>]

I read tolua++ manual and I found it pretty clear. I didn't understand, 
however, if I can make it work in the other direction: passing objects 
of known 'type' from C++ to a Lua function.

Example: if tolua++ knows of the C++ type "Thing", I need to pass a 
Thing object (not necessarily originating from Lua) from C++ to a Lua 
function and have Lua treat this value as if it were created by Thing:new().

In other words, I'd like to know how to push into a Lua stack a 
tolua++-recognized object+tag combination from the C++ side, if that's 
possible.

  Enrico