# List of partial functions

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Revision as of 17:17, 22 February 2019 by Josephcsible (talk | contribs) ("filter (const False) [1..]" and "dropWhile (const True) [1..]" are both bottom)

## Contents

## Partial functions in Prelude

### Functions that aren't even partial

- error
- undefined

### List functions

- maximum
- minimum
- head
- tail
- init
- last
- foldl (∞)
- foldl' (∞)
- foldl1
- foldl1'
- foldr1
- scanr (∞)
- scanr1 (∞)
- cycle
- !!
- filter (∞)
- dropWhile (∞)
- length (∞)
- sum (∞)
- product (∞)
- reverse (∞)

### Other

- read
- quot
- rem
- quotRem
- div
- mod
- divMod
- succ
- pred
- toEnum
- (^)
- fail
- ... (todo)

## Partial functions in other base libraries

### Data.List

- genericIndex
- genericLength (∞)

### Data.Map

- (!)

### Data.Maybe

- fromJust

## Partial functions in other Haskell Platform packages

... (todo)

NB. Functions marked with (∞) are partial because the function will not terminate if given an infinite list.