Function lua_absindex

3rd/lua-5.4.3/src/lapi.c:162–166

** convert an acceptable stack index into an absolute index */

** convert an acceptable stack index into an absolute index
*/
LUA_API int lua_absindex (lua_State *L, int idx) {
  return (idx > 0 || ispseudo(idx))
         ? idx
         : cast_int(L->top - L->ci->func) + idx;
}


LUA_API int lua_gettop (lua_State *L) {