Safe Haskell	Safe
Language	Haskell98

Data.List.Key

Description

Variant of Data.List functions like group, sort where the comparison is performed on a key computed from the list elements. In principle these functions could be replaced by e.g. sortBy (compare on f), but f will be re-computed for every comparison. If the evaluation of f is expensive, our functions are better, since they buffer the results of f.

Synopsis

nub :: Eq b => (a -> b) -> [a] -> [a]
sort :: Ord b => (a -> b) -> [a] -> [a]
minimum :: Ord b => (a -> b) -> [a] -> a
maximum :: Ord b => (a -> b) -> [a] -> a
group :: Eq b => (a -> b) -> [a] -> [[a]]
merge :: Ord b => (a -> b) -> [a] -> [a] -> [a]

Documentation

nub :: Eq b => (a -> b) -> [a] -> [a] Source #

sort :: Ord b => (a -> b) -> [a] -> [a] Source #

minimum :: Ord b => (a -> b) -> [a] -> a Source #

argmin

maximum :: Ord b => (a -> b) -> [a] -> a Source #

argmax

group :: Eq b => (a -> b) -> [a] -> [[a]] Source #

Divides a list into sublists such that the members in a sublist share the same key. It uses semantics of groupBy, not that of groupBy.

merge :: Ord b => (a -> b) -> [a] -> [a] -> [a] Source #