Re: Does anyone want intersperse for Data.Sequence?

Sequence is not used nearly enough. I think anything useful in the List API should also be in the Sequence API. On Sat, Dec 27, 2014 at 5:50 AM, David Feuer wrote:

Anyone else have an opinion? Bertram Felgenhauer pointed out to me that a friendlier-looking expression is

intersperse x xs = drop 1 $ fromList xs <**> fromList [const x, id]

but this still may not be the most obvious thing. The main question, I think, is whether anyone is likely to *use* an intersperse function for sequences. If so, I think we should add it; if not, probably not.

On Mon, Dec 22, 2014 at 7:11 AM, Felipe Lessa wrote:

...

On 22-12-2014 09:03, 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

If the name clash is the only downside, I'm +1. That intersperse definition isn't obvious :).

Cheers,

-- Felipe.

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