Function luaL_newmetatable

lua/lauxlib.c:144–153

LUALIB_API int luaL_newmetatable (lua_State *L, const char *tname) {
  lua_getfield(L, LUA_REGISTRYINDEX, tname);  /* get registry.name */
  if (!lua_isnil(L, -1))  /* name already in use? */
    return 0;  /* leave previous value on top, but return 0 */
  lua_pop(L, 1);
  lua_newtable(L);  /* create metatable */
  lua_pushvalue(L, -1);
  lua_setfield(L, LUA_REGISTRYINDEX, tname);  /* registry.name = metatable */
  return 1;
}


LUALIB_API void *luaL_checkudata (lua_State *L, int ud, const char *tname) {