utility-ht-0.0.8: Various small helper functions for Lists, Maybes, Tuples, Functions

Safe HaskellSafe-Infered

Data.Tuple.HT

Contents

Synopsis

Pair

mapPair :: (a -> c, b -> d) -> (a, b) -> (c, d)

Cf. '(Control.Arrow.***)'.

Apply two functions on corresponding values in a pair, where the pattern match on the pair constructor is lazy. This is crucial in recursions such as the of partition.

mapFst :: (a -> c) -> (a, b) -> (c, b)

mapSnd :: (b -> c) -> (a, b) -> (a, c)

swap :: (a, b) -> (b, a)

forcePair :: (a, b) -> (a, b)

Triple

fst3 :: (a, b, c) -> a

snd3 :: (a, b, c) -> b

thd3 :: (a, b, c) -> c

curry3 :: ((a, b, c) -> d) -> a -> b -> c -> d

uncurry3 :: (a -> b -> c -> d) -> (a, b, c) -> d