diff options
| -rw-r--r-- | StackSet.hs | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/StackSet.hs b/StackSet.hs index 654ff5d..3b23d59 100644 --- a/StackSet.hs +++ b/StackSet.hs @@ -324,9 +324,10 @@ integrate (Stack x l r) = reverse l ++ x : r integrate' :: Maybe (Stack a) -> [a] integrate' = maybe [] integrate --- | --- /O(n)/. Texture a list. --- +-- | +-- /O(n)/. Turn a list into a possibly empty stack (i.e., a zipper): +-- the first element of the list is current, and the rest of the list +-- is down. differentiate :: [a] -> Maybe (Stack a) differentiate [] = Nothing differentiate (x:xs) = Just $ Stack x [] xs |