úÎ Å x     Safe/2bDouble-ended queue (aka Dequeue or Deque) based on the head-tail linked list. Can be cycled. See  and .O(1).  is available from the  instance.O(1), occasionally O(n). 0» toList . shiftLeft $ fromList [1,2,3] [2,3,1] O(1), occasionally O(n). 1» toList . shiftRight $ fromList [1,2,3] [3,1,2] O(1). Prepend an element.O(1). Append an element.O(1), occasionally O(n).O(1), occasionally O(n). O(n). O(1). O(1), occasionally O(n). O(1), occasionally O(n). O(1), occasionally O(n).O(1), occasionally O(n).          deque-0.2-57qUsFIWRDHHIsegGQQI7JDequefromList shiftLeft shiftRightconssnocunconsunsnocprependreverseheadtailinitlast $fMonadDeque$fApplicativeDeque$fTraversableDeque$fFoldableDeque $fMonoidDeque$fFunctorDeque $fShowDeque $fEqDequebase Data.FoldabletoListFoldable