f# - Why there is no List.skip and List.take? -


why there no list.skip , list.take? there of course seq.take , seq.skip, not create lists result.

one possible solution is: mylist |> seq.skip n |> seq.tolist creates first enumerator new list enumerator. think there more direct way create immutable list immutable list. since there no copying of elements internally there references new list original one.

other possible solution (without throwing exceptions) is:

let rec listskip n xs =      match (n, xs)     | 0, _ -> xs     | _, [] -> []     | n, _::xs -> listskip (n-1) xs 

but still not answer question...

the would-be list.skip 1 called list.tail, can tail list n times.

list.take have create new list anyway, since common suffixes of immutable list can shared.


Comments

Popular posts from this blog

asp.net - repeatedly call AddImageUrl(url) to assemble pdf document -

java - Android recognize cell phone with keyboard or not? -

iphone - How would you achieve a LED Scrolling effect? -