Picking up the discard pile

Can a player pick up the discard pile in the following scenario:

Player has a 5 card meld on the table. She picks up the discard pile despite the fact that doing so gives her more than the 7 cards needed for a canasta since she already has 2 cards in her hand to complete the meld. And, she also gets the advantage of making additional melds or adding to the existing ones using remaining cards from the discard pile.