Re: generic imports? void* -> generics?

[chris <spamoff.danx@ntlworld.com>]

Another problem is that in this case the void* is a pointer to some data 
block... but if we define the following


with Lua_Types;                use Lua_Types;

generic
    type Userdata is private;
    type Userdata_Access is access all Userdata;

function Lua.To_Userdata (L   : in Lua_State_Access;
                           Pos : in Index) return Userdata_Access;

what will the interaction be with the c code?  It's not possible afaik 
to define the convention of Userdata_Access to C.

Can anyone please help?  I'm not really sure what the solution should be...

http://www.lua.org/manual/5.0/manual.html#3.8 describes the operation of 
this function ...


"lua_touserdata (see 3.5) retrieves the value of a userdata. When 
applied on a full userdata, it returns the address of its block; when 
applied on a light userdata, it returns its pointer; when applied on a 
non-userdata value, it returns NULL."