In playing 8-ball pool, if you have only your final object ball remaining, can you call the object ball and the 8-ball at the same time, as long as the object ball is pocketed first, and win the game?
(This post may be a duplicate of another one, see my comment, but I will include my answer to that one since that question is old and has a low likelihood of an answer being accepted. Perhaps this post will help others if it gets an accepted answer.)
One official source: WPA rulebook, located at this link:
Rule 3.8c says that the shooter loses if he pockets the eight ball in an uncalled pocket.
Furthermore, Rule 3.6 says that every shot must be called (except for the break) AND says that "The eight ball may be called only after the shot on which the shooter's group has been cleared from the table."
Therefore, you cannot possibly call the eight ball on a shot as you described. And since you did not call it, you lose.
(Side note about a common misconception in pool - If you look at rule 3.6a, if you're shooting at the eight ball you only lose on a scratch if you also pocket the eight ball. In other words, if you scratch but the eight ball doesn't go in, the game continues.)