| Safe Haskell | Trustworthy |
|---|---|
| Language | Haskell2010 |
Data.Monoid.Textual
Contents
Description
This module defines the TextualMonoid class and several of its instances.
Synopsis
- class (IsString t, LeftReductiveMonoid t, LeftGCDMonoid t, FactorialMonoid t) => TextualMonoid t where
Documentation
class (IsString t, LeftReductiveMonoid t, LeftGCDMonoid t, FactorialMonoid t) => TextualMonoid t where Source #
The TextualMonoid class is an extension of FactorialMonoid specialized for monoids that can contain
characters. Its methods are generally equivalent to their namesake functions from Data.List and Data.Text, and
they satisfy the following laws:
unfoldr splitCharacterPrefix . fromString == id splitCharacterPrefix . primePrefix == fmap (\(c, t)-> (c, mempty)) . splitCharacterPrefix map f . fromString == fromString . List.map f concatMap (fromString . f) . fromString == fromString . List.concatMap f foldl ft fc a . fromString == List.foldl fc a foldr ft fc a . fromString == List.foldr fc a foldl' ft fc a . fromString == List.foldl' fc a scanl f c . fromString == fromString . List.scanl f c scanr f c . fromString == fromString . List.scanr f c mapAccumL f a . fromString == fmap fromString . List.mapAccumL f a mapAccumL f a . fromString == fmap fromString . List.mapAccumL f a takeWhile pt pc . fromString == fromString . takeWhile pc dropWhile pt pc . fromString == fromString . dropWhile pc mconcat . intersperse (singleton c) . split (== c) == id find p . fromString == List.find p elem c . fromString == List.elem c
A TextualMonoid may contain non-character data insterspersed between its characters. Every class method that
returns a modified TextualMonoid instance generally preserves this non-character data. Methods like foldr can
access both the non-character and character data and expect two arguments for the two purposes. For each of these
methods there is also a simplified version with underscore in name (like foldr_) that ignores the non-character
data.
All of the following expressions are identities:
map id concatMap singleton foldl (<>) (\a c-> a <> singleton c) mempty foldr (<>) ((<>) . singleton) mempty foldl' (<>) (\a c-> a <> singleton c) mempty scanl1 (const id) scanr1 const uncurry (mapAccumL (,)) uncurry (mapAccumR (,)) takeWhile (const True) (const True) dropWhile (const False) (const False) toString undefined . fromString
Minimal complete definition
Methods
fromText :: Text -> t Source #
Contructs a new data type instance Like fromString, but from a Text input instead of String.
fromText == fromString . Text.unpack
singleton :: Char -> t Source #
Creates a prime monoid containing a single character.
singleton c == fromString [c]
splitCharacterPrefix :: t -> Maybe (Char, t) Source #
Specialized version of splitPrimePrefix. Every prime factor of a Textual monoid must consist of a
single character or no character at all.
characterPrefix :: t -> Maybe Char Source #
Extracts a single character that prefixes the monoid, if the monoid begins with a character. Otherwise returns
Nothing.
characterPrefix == fmap fst . splitCharacterPrefix
map :: (Char -> Char) -> t -> t Source #
Equivalent to map from Data.List with a Char -> Char function. Preserves all non-character data.
map f == concatMap (singleton . f)
concatMap :: (Char -> t) -> t -> t Source #
Equivalent to concatMap from Data.List with a Char -> String function. Preserves all non-character
data.
toString :: (t -> String) -> t -> String Source #
Returns the list of characters the monoid contains, after having the argument function convert all its non-character factors into characters.
any :: (Char -> Bool) -> t -> Bool Source #
all :: (Char -> Bool) -> t -> Bool Source #
foldl :: (a -> t -> a) -> (a -> Char -> a) -> a -> t -> a Source #
The first argument folds over the non-character prime factors, the second over characters. Otherwise equivalent
to foldl from Data.List.
foldl' :: (a -> t -> a) -> (a -> Char -> a) -> a -> t -> a Source #
Strict version of foldl.
foldr :: (t -> a -> a) -> (Char -> a -> a) -> a -> t -> a Source #
The first argument folds over the non-character prime factors, the second over characters. Otherwise equivalent to 'List.foldl\'' from Data.List.
scanl :: (Char -> Char -> Char) -> Char -> t -> t Source #
scanl1 :: (Char -> Char -> Char) -> t -> t Source #
Equivalent to scanl1 from Data.List when applied to a String, but preserves all non-character data.
scanl f c == scanl1 f . (singleton c <>)
scanr :: (Char -> Char -> Char) -> Char -> t -> t Source #
scanr1 :: (Char -> Char -> Char) -> t -> t Source #
Equivalent to scanr1 from Data.List when applied to a String, but preserves all non-character data.
scanr f c == scanr1 f . (<> singleton c)
mapAccumL :: (a -> Char -> (a, Char)) -> a -> t -> (a, t) Source #
Equivalent to mapAccumL from Data.List when applied to a String, but preserves all non-character
data.
mapAccumR :: (a -> Char -> (a, Char)) -> a -> t -> (a, t) Source #
Equivalent to mapAccumR from Data.List when applied to a String, but preserves all non-character
data.
takeWhile :: (t -> Bool) -> (Char -> Bool) -> t -> t Source #
The first predicate tests the non-character data, the second one the characters. Otherwise equivalent to
takeWhile from Data.List when applied to a String.
dropWhile :: (t -> Bool) -> (Char -> Bool) -> t -> t Source #
The first predicate tests the non-character data, the second one the characters. Otherwise equivalent to
dropWhile from Data.List when applied to a String.
break :: (t -> Bool) -> (Char -> Bool) -> t -> (t, t) Source #
'break pt pc' is equivalent to |span (not . pt) (not . pc)|.
span :: (t -> Bool) -> (Char -> Bool) -> t -> (t, t) Source #
'span pt pc t' is equivalent to |(takeWhile pt pc t, dropWhile pt pc t)|.
spanMaybe :: s -> (s -> t -> Maybe s) -> (s -> Char -> Maybe s) -> t -> (t, t, s) Source #
spanMaybe' :: s -> (s -> t -> Maybe s) -> (s -> Char -> Maybe s) -> t -> (t, t, s) Source #
Strict version of spanMaybe.
split :: (Char -> Bool) -> t -> [t] Source #
Splits the monoid into components delimited by character separators satisfying the given predicate. The characters satisfying the predicate are not a part of the result.
split p == Factorial.split (maybe False p . characterPrefix)
find :: (Char -> Bool) -> t -> Maybe Char Source #
elem :: Char -> t -> Bool Source #
foldl_ :: (a -> Char -> a) -> a -> t -> a Source #
foldl_ = foldl const
foldl_' :: (a -> Char -> a) -> a -> t -> a Source #
foldr_ :: (Char -> a -> a) -> a -> t -> a Source #
takeWhile_ :: Bool -> (Char -> Bool) -> t -> t Source #
takeWhile_ = takeWhile . const
dropWhile_ :: Bool -> (Char -> Bool) -> t -> t Source #
dropWhile_ = dropWhile . const
break_ :: Bool -> (Char -> Bool) -> t -> (t, t) Source #
break_ = break . const
span_ :: Bool -> (Char -> Bool) -> t -> (t, t) Source #
span_ = span . const
spanMaybe_ :: s -> (s -> Char -> Maybe s) -> t -> (t, t, s) Source #
spanMaybe_ s = spanMaybe s (const . Just)
spanMaybe_' :: s -> (s -> Char -> Maybe s) -> t -> (t, t, s) Source #