Add scanl'
The presence of foldl' and foldl1' suggests the addition of scanl' (and scanl1') to Data.List:
scanl' :: (a -> b -> a) -> a -> [b] -> [a]
scanl' f q ls = q `seq` (q : (case ls of
[] -> []
x:xs -> scanl' f (f q x) xs))
This would finally sort out the infamous (last . scanl) problem.
Trac metadata
Trac field | Value |
---|---|
Version | 7.7 |
Type | FeatureRequest |
TypeOfFailure | OtherFailure |
Priority | normal |
Resolution | Unresolved |
Component | libraries/base |
Test case | |
Differential revisions | |
BlockedBy | |
Related | |
Blocking | |
CC | mail@nh2.me |
Operating system | |
Architecture |