some lua questions

["Bryan Weingarten" <Bryan.Weingarten@...>]

hi,

i'm evaluating lua and i have a few outstanding questions.  

1. it's very clear from the documentation how to call lua from c and
register callbacks for lua to call.  but i don't see how to have lua
load and call functions in an external shared library that isn't part of
the host.  for example, how do i call a win32 function in the msvcrt.dll
or expat.dll?  is this possible?  or do i have to proxy every call
through a callback in the host?

2. one of my goals/requirments is that my host is a single shared
library with no other external files or dependencies.  so, if for
example, i want to include some lua code that isn't part of lualib.lib
how do i include it as part of my lua environment.  is it best to use
luac and embed the resulting binary code as binary data in the host then
have lua execute it?

3. is there a way from c to tell the difference between a lua variable
that contains binary data from a string?

4. is there a way from c to tell the difference between a lua variable
that contains an integer from a double?

thank you,

bryan