tails関数
https://hackage.haskell.org/package/base-4.21.0.0/docs/Data-List.html#v:tails
code:hs
tails ::
a
->
a
code:_
>> tails "abc"
"abc","bc","c",""
code:_
>> tails
1, 2, 3
1,2,3],
2,3
,
3
,[
定義例
code:hs
-- >>> tails'
1,2,3,4
--
1,2,3,4],
2,3,4
,
3,4
,
4
,[
tails' ::
a
->
a
tails' = scanr (:) []
scanr
を使って定義できる