[luatex] access defined Lua global variables in TeX macros

[Tim Li]

Hi, I am a newbie in LuaTeX but it's very interesting.  We can define a macro 
like this: \def\foo#1{%  \directlua{var = [[#1]]; tex.print(var)}  % can I 
access "var" below?  ...} can I access this global variable "var" in the other 
part of \foo?  Best regards,Tim