Question

I’m incorporating Lua scripting in my iPhone game implementation and it’s working great!

For purely cosmetic reasons, I’d like for my functions in Lua to be in the format of PN.function(). Currently they are in the format of function().

I’ve tried registering the function as such:

lua_register(lua, "PN.Color", Color);

But it won’t let me call it in the Lua script.

Anyone have any suggestions?

Thanks!

Answered my own question!:

lua_newtable(lua);
int pn = lua_gettop(lua);

lua_pushstring(lua, "Click");
lua_pushcfunction(lua, Click);
lua_settable(lua, pn);

lua_pushstring(lua, "Release");
lua_pushcfunction(lua, Release);
lua_settable(lua, pn);

lua_setglobal(lua, "PN");

Answer 1

You cannot use . as a function name in Lua. If you’re trying to put all of your Lua functions in a global table called PN, then you have to actually do that.

Remember: lua_register is just a macro:

 #define lua_register(L,n,f) \
        (lua_pushcfunction(L, f), lua_setglobal(L, n))

There’s nothing that say you couldn’t do it yourself more specifically.

If you have a global table PN that you want to register Lua functions into, you do the following:

1. Push the PN table onto the stack, using lua_getfield(L, LUA_GLOBALSINDEX, "PN").
2. Push the function you want to register onto the stack, with lua_pushcfunction(L, Color).
3. Put the function into the proper location in the table, with lua_setfield(L, -2, "Color").
4. Pop the table from the stack with lua_pop(L, 1).