Lua 5.2 doesn't have the lua_objlen function

[imzyxwvu]

From the Lua 5.2 manual:

Function lua_objlen was renamed lua_rawlen.

And in the common.h file:

#if LUA_VERSION_NUM < 502
/* lua_rawlen: Not entirely correct, but should work anyway */
#   define lua_rawlen lua_objlen
/* lua_...uservalue: Something very different, but it should get the job done */
#   define lua_getuservalue lua_getfenv
#   define lua_setuservalue lua_setfenv
#   define luaL_newlib(L,l) (lua_newtable(L), luaL_register(L,NULL,l))
#   define luaL_setfuncs(L,l,n) (assert(n==0), luaL_register(L,NULL,l))
#endif

So please replace lua_objlen with lua_rawlen and do not use it any more to make the code's compliance better.

By the way, lua_objlen is just lua_rawlen so that comment can be removed.