Math.Combinat.Helper

Miscellaneous helper functions

debugging

debug :: Show a => a -> b -> b

pairs

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

pairs :: [a] -> [(a, a)]

pairsWith :: (a -> a -> b) -> [a] -> [b]

lists

sum' :: Num a => [a] -> a

equality and ordering

equating :: Eq b => (a -> b) -> a -> a -> Bool

reverseOrdering :: Ordering -> Ordering

reverseCompare :: Ord a => a -> a -> Ordering

reverseSort :: Ord a => [a] -> [a]

groupSortBy :: (Eq b, Ord b) => (a -> b) -> [a] -> [[a]]

nubOrd :: Ord a => [a] -> [a]

first / last

mapWithLast :: (Bool -> a -> b) -> [a] -> [b]

The boolean argument will True only for the last element

mapWithFirst :: (Bool -> a -> b) -> [a] -> [b]

mapWithFirstLast :: (Bool -> Bool -> a -> b) -> [a] -> [b]

helpers for ASCII drawing

mkLinesUniformWidth :: [String] -> [String]

extend lines with spaces so that they have the same line

mkBlocksUniformHeight :: [[String]] -> [[String]]

mkUniformBlocks :: [[String]] -> [[String]]

hConcatLines :: [[String]] -> [String]

vConcatLines :: [[String]] -> [String]

counting

count :: Eq a => a -> [a] -> Int

histogram :: (Eq a, Ord a) => [a] -> [(a, Int)]

maybe

fromJust :: Maybe a -> a

bool

intToBool :: Int -> Bool

boolToInt :: Bool -> Int

iteration

nest :: Int -> (a -> a) -> a -> a

unfold1 :: (a -> Maybe a) -> a -> [a]

unfold :: (b -> (a, Maybe b)) -> b -> [a]

unfoldEither :: (b -> Either c (b, a)) -> b -> (c, [a])

unfoldM :: Monad m => (b -> m (a, Maybe b)) -> b -> m [a]

mapAccumM :: Monad m => (acc -> x -> m (acc, y)) -> acc -> [x] -> m (acc, [y])