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| Description | |||||||||||||
| Simple combinators working solely on and with functions. | |||||||||||||
| Synopsis | |||||||||||||
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| Prelude re-exports | |||||||||||||
| id :: a -> a | |||||||||||||
| Identity function. | |||||||||||||
| const :: a -> b -> a | |||||||||||||
| Constant function. | |||||||||||||
| (.) :: (b -> c) -> (a -> b) -> a -> c | |||||||||||||
| Function composition. | |||||||||||||
| flip :: (a -> b -> c) -> b -> a -> c | |||||||||||||
| flip f takes its (first) two arguments in the reverse order of f. | |||||||||||||
| ($) :: (a -> b) -> a -> b | |||||||||||||
Application operator. This operator is redundant, since ordinary application (f x) means the same as (f $ x). However, $ has low, right-associative binding precedence, so it sometimes allows parentheses to be omitted; for example: f $ g $ h x = f (g (h x)) It is also useful in higher-order situations, such as map ($ 0) xs, or Data.List.zipWith ($) fs xs. | |||||||||||||
| Other combinators | |||||||||||||
| fix :: (a -> a) -> a | |||||||||||||
| fix f is the least fixed point of the function f, i.e. the least defined x such that f x = x. | |||||||||||||
| on :: (b -> b -> c) -> (a -> b) -> a -> a -> c | |||||||||||||
(*) `on` f = \x y -> f x * f y. Typical usage: Data.List.sortBy (compare `on` fst). Algebraic properties: | |||||||||||||
| Produced by Haddock version 2.7.2 |