Coming back to your original question: I don't see any real points against adding it: 1. Name clashes Data.Sequence exports functions like `reverse`, `zip`, `length`, many more. That's an indicator to me that its API, like Data.Vector's, is meant to be imported qualified. 2. "It has same asymptotics but a better constant factor than X" How's that a point against? +1 On 22/12/14 12:03, David Feuer wrote:
containers master now uses a new mechanism to implement <*> that can also be used directly to implement an efficient intersperse function corresponding to the one in Data.List. The real question is whether anyone wants one. The potential for clashing names is obviously a point against. The other is that the same asymptotic bounds (but almost certainly worse constant factors) can be obtained using
intersperse x xs = drop 1 $ forwards $ Backwards (fromList [const x, id]) <*> Backwards xs