如何从C / C ++访问lua脚本中的局部变量或调用局部函数？

Question

If I define a "local" function, as such:

local function Dispatch(archive) coroutine.resume(yielder) end

...and I want to call this function from C++, I do not think I can use the lua_getglobal() call:

m_pThreadState = lua_newthread(m_MasterLuaState);
//Load/define the above "Dispatch" routine local to this thread.
luaL_loadbuffer(m_pThreadState, m_ScriptBody, strlen(m_ScriptBody),"Console");
lua_getglobal(m_pThreadState, "Dispatch"); //UH-OH!! PROBLEM HERE!!
lua_pcall(m_pThreadState, 1, 0, 0);

So how do I specify/push the local function "Dispatch" in preperation for the call? Again, I assume I cannot use the lua_getglobal() call, because the "Dispatch" function is defined as "local" to the m_pThreadState. What do I do?

Answer 1

You cannot access local variables from C (aside from debug API, but I don't think that's what you want).

Local variables (and functions, since they're variables) are what they are - local, ie accessible only from within their surrounding scope.

So you're left with two options:

• create a global variable
• call a C function from Lua and pass the local function as a parameter. Then you will have the function on the stack and will be able to call it from C (from within the C function). Now there is little point in doing that, I was just merely pointing at the way it could be done.