Convenience functions for working with tuples.
Tuple, but for 3-tuples (e.g. Tuple.first (1, 2) == Tuple.Extra.first (1, 2, 3) == 1)swap, reverse, rotateLeft, rotateRight, swapFirst, swapLast)Tuple.pair, provides pairTo, double and tripleuncurry2 List.repeat (2, 'a') == List repeat 2 'a')