Safe Haskell	None
Language	Haskell2010

Data.Tax

Contents

Overview
API
Re-exports

Description

This library provides combinators for constructing taxes. It is based on the dollaridoos library.

Synopsis

newtype Tax a b = Tax {
- getTax :: a -> b
}
type MoneyTax a = Tax (Money a) (Money a)
lump :: a -> Tax b a
flat :: Num a => a -> Tax (Money a) (Money a)
threshold :: (Num a, Ord a) => Money a -> a -> Tax (Money a) (Money a)
threshold' :: (Ord b, Monoid a) => b -> Tax b a -> Tax b a
thresholds :: (Num a, Ord a) => [(Money a, a)] -> Tax (Money a) (Money a)
above :: (Num a, Ord a) => Money a -> a -> Tax (Money a) (Money a)
above' :: (Num b, Ord b) => Money b -> Tax (Money b) a -> Tax (Money b) a
marginal :: (Num a, Ord a) => [(Money a, a)] -> Tax (Money a) (Money a)
lesserOf :: Ord a => Tax b a -> Tax b a -> Tax b a
greaterOf :: Ord a => Tax b a -> Tax b a -> Tax b a
limit :: Ord a => a -> Tax b a -> Tax b a
effective :: Fractional a => Money a -> Tax (Money a) (Money a) -> Tax (Money a) (Money a)
module Data.Money
class Semigroup a where
- (<>) :: a -> a -> a
- sconcat :: NonEmpty a -> a
- stimes :: Integral b => b -> a -> a
class Semigroup a => Monoid a where
- mempty :: a
- mappend :: a -> a -> a
- mconcat :: [a] -> a
class Profunctor (p :: Type -> Type -> Type) where
- dimap :: (a -> b) -> (c -> d) -> p b c -> p a d
- lmap :: (a -> b) -> p b c -> p a c
- rmap :: (b -> c) -> p a b -> p a c

Overview

The most basic tax is a flat rate tax:

businessTax = flat 0.3

To compute the tax, use getTax:

λ> getTax businessTax (Money 1000000)
$300000.0

Taxes form a semigroup (sum of tax outputs) and monoid:

λ> getTax (flat 0.1 <> flat 0.2) (Money 10)
$3.0
λ> getTax mempty (Money 10)
$0

Progressive taxes can be constructed using the above combinator, which taxes the amount above a given threshold at a flat rate.

individualIncomeTax =
     above (Money 18200 ) (0.19  - 0     )
  <> above (Money 45000 ) (0.325 - 0.19  )
  <> above (Money 120000) (0.37  - 0.325 )
  <> above (Money 180000) (0.45 - 0.37   )

The marginal function provides a shorthand for the above.

individualIncomeTax = marginal
  [ ( Money 18200,  0.19  - 0     )
  , ( Money 45000,  0.325 - 0.19  )
  , ( Money 120000, 0.37  - 0.325 )
  , ( Money 180000, 0.45  - 0.37  ) ]

Taxes can be negative. For example, the lump, above and limit combinators can be used to construct a low-income tax offset that starts at $445 and reduces at a rate of 1.5c per dollar earned over $37000:

lowIncomeTaxOffset =
  limit mempty
  (lump (Money (-445)) <> above (Money 37000) 0.015)

The threshold combinator applies a tax to the full input amount, if it exceeds the threshold.

medicareLevySurcharge =
     threshold (review money 90000 ) 0.0100
  <> threshold (review money 105000) 0.0025
  <> threshold (review money 140000) 0.0025

Some taxes have "shade-in" where the amount above some threshold is taxed at a higher rate to "catch up" to some lower flat rate. The above and lesserOf combinators can be used to construct this tax:

medicareLevy l = lesserOf (above l 0.1) (flat 0.02)

Although some of the combinators deal directory with Money, a Tax can be defined for other types. For example, you can tax a person a certain number of days labour, based on their age.

data Sex = M | F
newtype Years = Years Int
newtype Days = Days Int
data Person = Person Years Sex

corvée :: Tax Person Days
corvée = Tax f
  where
  f (Person (Years age) sex) = Days $ if age >= 18 && age <= maxAge sex then 10 else 0
  maxAge sex = case sex of M -> 45 ; F -> 35

API

newtype Tax a b Source #

A function from an amount or value subject to taxation, to the amount or value of tax due.

Taxes form a semigroup where the tax payable is the sum of tax payable of consituent taxes.

Taxes form a monoid where the identity is a tax of 0%

Taxes are a profunctor, making it trivial to perform simple transformations of the input and/or output (e.g. rounding down to whole dollars).

Constructors

Tax
Fields getTax :: a -> b

Instances

Instances details

Profunctor Tax Source #
Instance details Defined in Data.Tax Methods dimap :: (a -> b) -> (c -> d) -> Tax b c -> Tax a d # lmap :: (a -> b) -> Tax b c -> Tax a c # rmap :: (b -> c) -> Tax a b -> Tax a c # (#.) :: forall a b c q. Coercible c b => q b c -> Tax a b -> Tax a c # (.#) :: forall a b c q. Coercible b a => Tax b c -> q a b -> Tax a c #
Functor (Tax a) Source #
Instance details Defined in Data.Tax Methods fmap :: (a0 -> b) -> Tax a a0 -> Tax a b # (<$) :: a0 -> Tax a b -> Tax a a0 #
Monoid b => Monoid (Tax a b) Source #
Instance details Defined in Data.Tax Methods mempty :: Tax a b # mappend :: Tax a b -> Tax a b -> Tax a b # mconcat :: [Tax a b] -> Tax a b #
Semigroup b => Semigroup (Tax a b) Source #
Instance details Defined in Data.Tax Methods (<>) :: Tax a b -> Tax a b -> Tax a b # sconcat :: NonEmpty (Tax a b) -> Tax a b # stimes :: Integral b0 => b0 -> Tax a b -> Tax a b #

type MoneyTax a = Tax (Money a) (Money a) Source #

Convenience synonym for working with Money

lump :: a -> Tax b a Source #

A lump-sum tax; a fixed value (ignores input).

flat :: Num a => a -> Tax (Money a) (Money a) Source #

Construct a flat rate tax with no threshold

threshold :: (Num a, Ord a) => Money a -> a -> Tax (Money a) (Money a) Source #

Tax full amount at flat rate if input >= threshold

threshold' :: (Ord b, Monoid a) => b -> Tax b a -> Tax b a Source #

Levy the tax if input >= threshold, otherwise don't

thresholds :: (Num a, Ord a) => [(Money a, a)] -> Tax (Money a) (Money a) Source #

Convert a [(threshold, rate)] into a flat tax whose rate is the sum of the rates that apply for a given input. The rates are cumulative. For example, if you want to tax people earning >$30,000 20%, and people earning >$50,000 30%, you only tax an extra 10% at 50000:

tax = thresholds [(30000, 0.2), (50000, 0.1)]

above :: (Num a, Ord a) => Money a -> a -> Tax (Money a) (Money a) Source #

Tax the amount exceeding the threshold at a flat rate.

above' :: (Num b, Ord b) => Money b -> Tax (Money b) a -> Tax (Money b) a Source #

Tax the amount exceeding the threshold

marginal :: (Num a, Ord a) => [(Money a, a)] -> Tax (Money a) (Money a) Source #

Convert a [(threshold, rate)] into a progressive tax. The rates are cumulative, i.e. the top marginal rate is the sum of the rates that apply for a given input.

lesserOf :: Ord a => Tax b a -> Tax b a -> Tax b a Source #

Levy the lesser of two taxes

greaterOf :: Ord a => Tax b a -> Tax b a -> Tax b a Source #

Levy the greater of two taxes

limit :: Ord a => a -> Tax b a -> Tax b a Source #

Limit the tax payable to the given amount

This could be used e.g. to limit a compulsory loan repayment to the balance of the loan, or ensure a (negative) tax offset does not become a (positive) tax.

effective :: Fractional a => Money a -> Tax (Money a) (Money a) -> Tax (Money a) (Money a) Source #

Given a tax and an amount construct the effective flat tax rate

Re-exports

module Data.Money

class Semigroup a where #

The class of semigroups (types with an associative binary operation).

Instances should satisfy the following:

Associativity: x <> (y <> z) = (x <> y) <> z

You can alternatively define sconcat instead of (<>), in which case the laws are:

Unit: sconcat (pure x) = x
Multiplication: sconcat (join xss) = sconcat (fmap sconcat xss)

Since: base-4.9.0.0

Minimal complete definition

(<>) | sconcat

Methods

(<>) :: a -> a -> a infixr 6 #

An associative operation.

Examples

Expand

>>> [1,2,3] <> [4,5,6]
[1,2,3,4,5,6]

>>> Just [1, 2, 3] <> Just [4, 5, 6]
Just [1,2,3,4,5,6]

>>> putStr "Hello, " <> putStrLn "World!"
Hello, World!

sconcat :: NonEmpty a -> a #

Reduce a non-empty list with <>

The default definition should be sufficient, but this can be overridden for efficiency.

Examples

Expand

For the following examples, we will assume that we have:

>>> import Data.List.NonEmpty (NonEmpty (..))

>>> sconcat $ "Hello" :| [" ", "Haskell", "!"]
"Hello Haskell!"

>>> sconcat $ Just [1, 2, 3] :| [Nothing, Just [4, 5, 6]]
Just [1,2,3,4,5,6]

>>> sconcat $ Left 1 :| [Right 2, Left 3, Right 4]
Right 2

stimes :: Integral b => b -> a -> a #

Repeat a value n times.

The default definition will raise an exception for a multiplier that is <= 0. This may be overridden with an implementation that is total. For monoids it is preferred to use stimesMonoid.

By making this a member of the class, idempotent semigroups and monoids can upgrade this to execute in $\mathcal{O}(1)$ by picking stimes = stimesIdempotent or stimes = stimesIdempotentMonoid respectively.

Examples

Expand

>>> stimes 4 [1]
[1,1,1,1]

>>> stimes 5 (putStr "hi!")
hi!hi!hi!hi!hi!

>>> stimes 3 (Right ":)")
Right ":)"

Instances

Instances details

Semigroup ByteArray	Since: base-4.17.0.0
Instance details Defined in Data.Array.Byte Methods (<>) :: ByteArray -> ByteArray -> ByteArray # sconcat :: NonEmpty ByteArray -> ByteArray # stimes :: Integral b => b -> ByteArray -> ByteArray #
Semigroup Void	Since: base-4.9.0.0
Instance details Defined in GHC.Base Methods (<>) :: Void -> Void -> Void # sconcat :: NonEmpty Void -> Void # stimes :: Integral b => b -> Void -> Void #
Semigroup Ordering	Since: base-4.9.0.0
Instance details Defined in GHC.Base Methods (<>) :: Ordering -> Ordering -> Ordering # sconcat :: NonEmpty Ordering -> Ordering # stimes :: Integral b => b -> Ordering -> Ordering #
Semigroup ()	Since: base-4.9.0.0
Instance details Defined in GHC.Base Methods (<>) :: () -> () -> () # sconcat :: NonEmpty () -> () # stimes :: Integral b => b -> () -> () #
Bits a => Semigroup (And a)	Since: base-4.16
Instance details Defined in Data.Bits Methods (<>) :: And a -> And a -> And a # sconcat :: NonEmpty (And a) -> And a # stimes :: Integral b => b -> And a -> And a #
FiniteBits a => Semigroup (Iff a)	This constraint is arguably too strong. However, as some types (such as `Natural`) have undefined `complement`, this is the only safe choice. Since: base-4.16
Instance details Defined in Data.Bits Methods (<>) :: Iff a -> Iff a -> Iff a # sconcat :: NonEmpty (Iff a) -> Iff a # stimes :: Integral b => b -> Iff a -> Iff a #
Bits a => Semigroup (Ior a)	Since: base-4.16
Instance details Defined in Data.Bits Methods (<>) :: Ior a -> Ior a -> Ior a # sconcat :: NonEmpty (Ior a) -> Ior a # stimes :: Integral b => b -> Ior a -> Ior a #
Bits a => Semigroup (Xor a)	Since: base-4.16
Instance details Defined in Data.Bits Methods (<>) :: Xor a -> Xor a -> Xor a # sconcat :: NonEmpty (Xor a) -> Xor a # stimes :: Integral b => b -> Xor a -> Xor a #
Semigroup (FromMaybe b)
Instance details Defined in Data.Foldable1 Methods (<>) :: FromMaybe b -> FromMaybe b -> FromMaybe b # sconcat :: NonEmpty (FromMaybe b) -> FromMaybe b # stimes :: Integral b0 => b0 -> FromMaybe b -> FromMaybe b #
Semigroup a => Semigroup (JoinWith a)
Instance details Defined in Data.Foldable1 Methods (<>) :: JoinWith a -> JoinWith a -> JoinWith a # sconcat :: NonEmpty (JoinWith a) -> JoinWith a # stimes :: Integral b => b -> JoinWith a -> JoinWith a #
Semigroup (NonEmptyDList a)
Instance details Defined in Data.Foldable1 Methods (<>) :: NonEmptyDList a -> NonEmptyDList a -> NonEmptyDList a # sconcat :: NonEmpty (NonEmptyDList a) -> NonEmptyDList a # stimes :: Integral b => b -> NonEmptyDList a -> NonEmptyDList a #
Semigroup (Comparison a)	`(<>)` on comparisons combines results with `(<>) @Ordering`. Without newtypes this equals `liftA2 (liftA2 (<>))`. (<>) :: Comparison a -> Comparison a -> Comparison a Comparison cmp <> Comparison cmp' = Comparison a a' -> cmp a a' <> cmp a a'
Instance details Defined in Data.Functor.Contravariant Methods (<>) :: Comparison a -> Comparison a -> Comparison a # sconcat :: NonEmpty (Comparison a) -> Comparison a # stimes :: Integral b => b -> Comparison a -> Comparison a #
Semigroup (Equivalence a)	`(<>)` on equivalences uses logical conjunction `(&&)` on the results. Without newtypes this equals `liftA2 (liftA2 (&&))`. (<>) :: Equivalence a -> Equivalence a -> Equivalence a Equivalence equiv <> Equivalence equiv' = Equivalence a b -> equiv a b && equiv' a b
Instance details Defined in Data.Functor.Contravariant Methods (<>) :: Equivalence a -> Equivalence a -> Equivalence a # sconcat :: NonEmpty (Equivalence a) -> Equivalence a # stimes :: Integral b => b -> Equivalence a -> Equivalence a #
Semigroup (Predicate a)	`(<>)` on predicates uses logical conjunction `(&&)` on the results. Without newtypes this equals `liftA2 (&&)`. (<>) :: Predicate a -> Predicate a -> Predicate a Predicate pred <> Predicate pred' = Predicate a -> pred a && pred' a
Instance details Defined in Data.Functor.Contravariant Methods (<>) :: Predicate a -> Predicate a -> Predicate a # sconcat :: NonEmpty (Predicate a) -> Predicate a # stimes :: Integral b => b -> Predicate a -> Predicate a #
Semigroup a => Semigroup (Identity a)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Identity Methods (<>) :: Identity a -> Identity a -> Identity a # sconcat :: NonEmpty (Identity a) -> Identity a # stimes :: Integral b => b -> Identity a -> Identity a #
Semigroup (First a)	Since: base-4.9.0.0
Instance details Defined in Data.Monoid Methods (<>) :: First a -> First a -> First a # sconcat :: NonEmpty (First a) -> First a # stimes :: Integral b => b -> First a -> First a #
Semigroup (Last a)	Since: base-4.9.0.0
Instance details Defined in Data.Monoid Methods (<>) :: Last a -> Last a -> Last a # sconcat :: NonEmpty (Last a) -> Last a # stimes :: Integral b => b -> Last a -> Last a #
Semigroup a => Semigroup (Down a)	Since: base-4.11.0.0
Instance details Defined in Data.Ord Methods (<>) :: Down a -> Down a -> Down a # sconcat :: NonEmpty (Down a) -> Down a # stimes :: Integral b => b -> Down a -> Down a #
Semigroup (First a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods (<>) :: First a -> First a -> First a # sconcat :: NonEmpty (First a) -> First a # stimes :: Integral b => b -> First a -> First a #
Semigroup (Last a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods (<>) :: Last a -> Last a -> Last a # sconcat :: NonEmpty (Last a) -> Last a # stimes :: Integral b => b -> Last a -> Last a #
Ord a => Semigroup (Max a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods (<>) :: Max a -> Max a -> Max a # sconcat :: NonEmpty (Max a) -> Max a # stimes :: Integral b => b -> Max a -> Max a #
Ord a => Semigroup (Min a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods (<>) :: Min a -> Min a -> Min a # sconcat :: NonEmpty (Min a) -> Min a # stimes :: Integral b => b -> Min a -> Min a #
Monoid m => Semigroup (WrappedMonoid m)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods (<>) :: WrappedMonoid m -> WrappedMonoid m -> WrappedMonoid m # sconcat :: NonEmpty (WrappedMonoid m) -> WrappedMonoid m # stimes :: Integral b => b -> WrappedMonoid m -> WrappedMonoid m #
Semigroup (NonEmpty a)	Since: base-4.9.0.0
Instance details Defined in GHC.Base Methods (<>) :: NonEmpty a -> NonEmpty a -> NonEmpty a # sconcat :: NonEmpty (NonEmpty a) -> NonEmpty a # stimes :: Integral b => b -> NonEmpty a -> NonEmpty a #
Semigroup a => Semigroup (STM a)	Since: base-4.17.0.0
Instance details Defined in GHC.Conc.Sync Methods (<>) :: STM a -> STM a -> STM a # sconcat :: NonEmpty (STM a) -> STM a # stimes :: Integral b => b -> STM a -> STM a #
(Generic a, Semigroup (Rep a ())) => Semigroup (Generically a)	Since: base-4.17.0.0
Instance details Defined in GHC.Generics Methods (<>) :: Generically a -> Generically a -> Generically a # sconcat :: NonEmpty (Generically a) -> Generically a # stimes :: Integral b => b -> Generically a -> Generically a #
Semigroup p => Semigroup (Par1 p)	Since: base-4.12.0.0
Instance details Defined in GHC.Generics Methods (<>) :: Par1 p -> Par1 p -> Par1 p # sconcat :: NonEmpty (Par1 p) -> Par1 p # stimes :: Integral b => b -> Par1 p -> Par1 p #
Num a => Semigroup (Money a)
Instance details Defined in Data.Money Methods (<>) :: Money a -> Money a -> Money a # sconcat :: NonEmpty (Money a) -> Money a # stimes :: Integral b => b -> Money a -> Money a #
Semigroup a => Semigroup (IO a)	Since: base-4.10.0.0
Instance details Defined in GHC.Base Methods (<>) :: IO a -> IO a -> IO a # sconcat :: NonEmpty (IO a) -> IO a # stimes :: Integral b => b -> IO a -> IO a #
Semigroup a => Semigroup (Maybe a)	Since: base-4.9.0.0
Instance details Defined in GHC.Base Methods (<>) :: Maybe a -> Maybe a -> Maybe a # sconcat :: NonEmpty (Maybe a) -> Maybe a # stimes :: Integral b => b -> Maybe a -> Maybe a #
Semigroup a => Semigroup (Solo a)	Since: base-4.15
Instance details Defined in GHC.Base Methods (<>) :: Solo a -> Solo a -> Solo a # sconcat :: NonEmpty (Solo a) -> Solo a # stimes :: Integral b => b -> Solo a -> Solo a #
Semigroup [a]	Since: base-4.9.0.0
Instance details Defined in GHC.Base Methods (<>) :: [a] -> [a] -> [a] # sconcat :: NonEmpty [a] -> [a] # stimes :: Integral b => b -> [a] -> [a] #
Semigroup (Either a b)	Since: base-4.9.0.0
Instance details Defined in Data.Either Methods (<>) :: Either a b -> Either a b -> Either a b # sconcat :: NonEmpty (Either a b) -> Either a b # stimes :: Integral b0 => b0 -> Either a b -> Either a b #
Semigroup a => Semigroup (Op a b)	`(<>) @(Op a b)` without newtypes is `(<>) @(b->a)` = `liftA2 (<>)`. This lifts the `Semigroup` operation `(<>)` over the output of `a`. (<>) :: Op a b -> Op a b -> Op a b Op f <> Op g = Op a -> f a <> g a
Instance details Defined in Data.Functor.Contravariant Methods (<>) :: Op a b -> Op a b -> Op a b # sconcat :: NonEmpty (Op a b) -> Op a b # stimes :: Integral b0 => b0 -> Op a b -> Op a b #
Semigroup (Proxy s)	Since: base-4.9.0.0
Instance details Defined in Data.Proxy Methods (<>) :: Proxy s -> Proxy s -> Proxy s # sconcat :: NonEmpty (Proxy s) -> Proxy s # stimes :: Integral b => b -> Proxy s -> Proxy s #
Semigroup (U1 p)	Since: base-4.12.0.0
Instance details Defined in GHC.Generics Methods (<>) :: U1 p -> U1 p -> U1 p # sconcat :: NonEmpty (U1 p) -> U1 p # stimes :: Integral b => b -> U1 p -> U1 p #
Semigroup (V1 p)	Since: base-4.12.0.0
Instance details Defined in GHC.Generics Methods (<>) :: V1 p -> V1 p -> V1 p # sconcat :: NonEmpty (V1 p) -> V1 p # stimes :: Integral b => b -> V1 p -> V1 p #
Semigroup a => Semigroup (ST s a)	Since: base-4.11.0.0
Instance details Defined in GHC.ST Methods (<>) :: ST s a -> ST s a -> ST s a # sconcat :: NonEmpty (ST s a) -> ST s a # stimes :: Integral b => b -> ST s a -> ST s a #
Semigroup b => Semigroup (Tax a b) Source #
Instance details Defined in Data.Tax Methods (<>) :: Tax a b -> Tax a b -> Tax a b # sconcat :: NonEmpty (Tax a b) -> Tax a b # stimes :: Integral b0 => b0 -> Tax a b -> Tax a b #
(Semigroup a, Semigroup b) => Semigroup (a, b)	Since: base-4.9.0.0
Instance details Defined in GHC.Base Methods (<>) :: (a, b) -> (a, b) -> (a, b) # sconcat :: NonEmpty (a, b) -> (a, b) # stimes :: Integral b0 => b0 -> (a, b) -> (a, b) #
Semigroup b => Semigroup (a -> b)	Since: base-4.9.0.0
Instance details Defined in GHC.Base Methods (<>) :: (a -> b) -> (a -> b) -> a -> b # sconcat :: NonEmpty (a -> b) -> a -> b # stimes :: Integral b0 => b0 -> (a -> b) -> a -> b #
Semigroup a => Semigroup (Const a b)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Const Methods (<>) :: Const a b -> Const a b -> Const a b # sconcat :: NonEmpty (Const a b) -> Const a b # stimes :: Integral b0 => b0 -> Const a b -> Const a b #
(Applicative f, Semigroup a) => Semigroup (Ap f a)	Since: base-4.12.0.0
Instance details Defined in Data.Monoid Methods (<>) :: Ap f a -> Ap f a -> Ap f a # sconcat :: NonEmpty (Ap f a) -> Ap f a # stimes :: Integral b => b -> Ap f a -> Ap f a #
Semigroup (f p) => Semigroup (Rec1 f p)	Since: base-4.12.0.0
Instance details Defined in GHC.Generics Methods (<>) :: Rec1 f p -> Rec1 f p -> Rec1 f p # sconcat :: NonEmpty (Rec1 f p) -> Rec1 f p # stimes :: Integral b => b -> Rec1 f p -> Rec1 f p #
(Profunctor p, Arrow p, Semigroup b) => Semigroup (Closure p a b)
Instance details Defined in Data.Profunctor.Closed Methods (<>) :: Closure p a b -> Closure p a b -> Closure p a b # sconcat :: NonEmpty (Closure p a b) -> Closure p a b # stimes :: Integral b0 => b0 -> Closure p a b -> Closure p a b #
ArrowPlus p => Semigroup (Tambara p a b)
Instance details Defined in Data.Profunctor.Strong Methods (<>) :: Tambara p a b -> Tambara p a b -> Tambara p a b # sconcat :: NonEmpty (Tambara p a b) -> Tambara p a b # stimes :: Integral b0 => b0 -> Tambara p a b -> Tambara p a b #
(Semigroup a, Semigroup b, Semigroup c) => Semigroup (a, b, c)	Since: base-4.9.0.0
Instance details Defined in GHC.Base Methods (<>) :: (a, b, c) -> (a, b, c) -> (a, b, c) # sconcat :: NonEmpty (a, b, c) -> (a, b, c) # stimes :: Integral b0 => b0 -> (a, b, c) -> (a, b, c) #
(Semigroup (f a), Semigroup (g a)) => Semigroup (Product f g a)	Since: base-4.16.0.0
Instance details Defined in Data.Functor.Product Methods (<>) :: Product f g a -> Product f g a -> Product f g a # sconcat :: NonEmpty (Product f g a) -> Product f g a # stimes :: Integral b => b -> Product f g a -> Product f g a #
(Semigroup (f p), Semigroup (g p)) => Semigroup ((f :*: g) p)	Since: base-4.12.0.0
Instance details Defined in GHC.Generics Methods (<>) :: (f :: g) p -> (f :: g) p -> (f :: g) p # sconcat :: NonEmpty ((f :: g) p) -> (f :: g) p # stimes :: Integral b => b -> (f :: g) p -> (f :*: g) p #
Semigroup c => Semigroup (K1 i c p)	Since: base-4.12.0.0
Instance details Defined in GHC.Generics Methods (<>) :: K1 i c p -> K1 i c p -> K1 i c p # sconcat :: NonEmpty (K1 i c p) -> K1 i c p # stimes :: Integral b => b -> K1 i c p -> K1 i c p #
Semigroup r => Semigroup (Forget r a b)	Via `Semigroup r => (a -> r)` Since: profunctors-5.6.2
Instance details Defined in Data.Profunctor.Types Methods (<>) :: Forget r a b -> Forget r a b -> Forget r a b # sconcat :: NonEmpty (Forget r a b) -> Forget r a b # stimes :: Integral b0 => b0 -> Forget r a b -> Forget r a b #
(Semigroup a, Semigroup b, Semigroup c, Semigroup d) => Semigroup (a, b, c, d)	Since: base-4.9.0.0
Instance details Defined in GHC.Base Methods (<>) :: (a, b, c, d) -> (a, b, c, d) -> (a, b, c, d) # sconcat :: NonEmpty (a, b, c, d) -> (a, b, c, d) # stimes :: Integral b0 => b0 -> (a, b, c, d) -> (a, b, c, d) #
Semigroup (f (g a)) => Semigroup (Compose f g a)	Since: base-4.16.0.0
Instance details Defined in Data.Functor.Compose Methods (<>) :: Compose f g a -> Compose f g a -> Compose f g a # sconcat :: NonEmpty (Compose f g a) -> Compose f g a # stimes :: Integral b => b -> Compose f g a -> Compose f g a #
Semigroup (f (g p)) => Semigroup ((f :.: g) p)	Since: base-4.12.0.0
Instance details Defined in GHC.Generics Methods (<>) :: (f :.: g) p -> (f :.: g) p -> (f :.: g) p # sconcat :: NonEmpty ((f :.: g) p) -> (f :.: g) p # stimes :: Integral b => b -> (f :.: g) p -> (f :.: g) p #
Semigroup (f p) => Semigroup (M1 i c f p)	Since: base-4.12.0.0
Instance details Defined in GHC.Generics Methods (<>) :: M1 i c f p -> M1 i c f p -> M1 i c f p # sconcat :: NonEmpty (M1 i c f p) -> M1 i c f p # stimes :: Integral b => b -> M1 i c f p -> M1 i c f p #
(Semigroup a, Semigroup b, Semigroup c, Semigroup d, Semigroup e) => Semigroup (a, b, c, d, e)	Since: base-4.9.0.0
Instance details Defined in GHC.Base Methods (<>) :: (a, b, c, d, e) -> (a, b, c, d, e) -> (a, b, c, d, e) # sconcat :: NonEmpty (a, b, c, d, e) -> (a, b, c, d, e) # stimes :: Integral b0 => b0 -> (a, b, c, d, e) -> (a, b, c, d, e) #

class Semigroup a => Monoid a where #

The class of monoids (types with an associative binary operation that has an identity). Instances should satisfy the following:

Right identity: x <> mempty = x
Left identity: mempty <> x = x
Associativity: x <> (y <> z) = (x <> y) <> z (Semigroup law)
Concatenation: mconcat = foldr (<>) mempty

You can alternatively define mconcat instead of mempty, in which case the laws are:

Unit: mconcat (pure x) = x
Multiplication: mconcat (join xss) = mconcat (fmap mconcat xss)
Subclass: mconcat (toList xs) = sconcat xs

The method names refer to the monoid of lists under concatenation, but there are many other instances.

Some types can be viewed as a monoid in more than one way, e.g. both addition and multiplication on numbers. In such cases we often define newtypes and make those instances of Monoid, e.g. Sum and Product.

NOTE: Semigroup is a superclass of Monoid since base-4.11.0.0.

Minimal complete definition

mempty | mconcat

Methods

mempty :: a #

Identity of mappend

Examples

Expand

>>> "Hello world" <> mempty
"Hello world"

>>> mempty <> [1, 2, 3]
[1,2,3]

mappend :: a -> a -> a #

An associative operation

NOTE: This method is redundant and has the default implementation mappend = (<>) since base-4.11.0.0. Should it be implemented manually, since mappend is a synonym for (<>), it is expected that the two functions are defined the same way. In a future GHC release mappend will be removed from Monoid.

mconcat :: [a] -> a #

Fold a list using the monoid.

For most types, the default definition for mconcat will be used, but the function is included in the class definition so that an optimized version can be provided for specific types.

>>> mconcat ["Hello", " ", "Haskell", "!"]
"Hello Haskell!"

Instances

Instances details

Monoid ByteArray	Since: base-4.17.0.0
Instance details Defined in Data.Array.Byte Methods mempty :: ByteArray # mappend :: ByteArray -> ByteArray -> ByteArray # mconcat :: [ByteArray] -> ByteArray #
Monoid Ordering	Since: base-2.1
Instance details Defined in GHC.Base Methods mempty :: Ordering # mappend :: Ordering -> Ordering -> Ordering # mconcat :: [Ordering] -> Ordering #
Monoid ()	Since: base-2.1
Instance details Defined in GHC.Base Methods mempty :: () # mappend :: () -> () -> () # mconcat :: [()] -> () #
FiniteBits a => Monoid (And a)	This constraint is arguably too strong. However, as some types (such as `Natural`) have undefined `complement`, this is the only safe choice. Since: base-4.16
Instance details Defined in Data.Bits Methods mempty :: And a # mappend :: And a -> And a -> And a # mconcat :: [And a] -> And a #
FiniteBits a => Monoid (Iff a)	This constraint is arguably too strong. However, as some types (such as `Natural`) have undefined `complement`, this is the only safe choice. Since: base-4.16
Instance details Defined in Data.Bits Methods mempty :: Iff a # mappend :: Iff a -> Iff a -> Iff a # mconcat :: [Iff a] -> Iff a #
Bits a => Monoid (Ior a)	Since: base-4.16
Instance details Defined in Data.Bits Methods mempty :: Ior a # mappend :: Ior a -> Ior a -> Ior a # mconcat :: [Ior a] -> Ior a #
Bits a => Monoid (Xor a)	Since: base-4.16
Instance details Defined in Data.Bits Methods mempty :: Xor a # mappend :: Xor a -> Xor a -> Xor a # mconcat :: [Xor a] -> Xor a #
Monoid (Comparison a)	`mempty` on comparisons always returns `EQ`. Without newtypes this equals `pure (pure EQ)`. mempty :: Comparison a mempty = Comparison _ _ -> EQ
Instance details Defined in Data.Functor.Contravariant Methods mempty :: Comparison a # mappend :: Comparison a -> Comparison a -> Comparison a # mconcat :: [Comparison a] -> Comparison a #
Monoid (Equivalence a)	`mempty` on equivalences always returns `True`. Without newtypes this equals `pure (pure True)`. mempty :: Equivalence a mempty = Equivalence _ _ -> True
Instance details Defined in Data.Functor.Contravariant Methods mempty :: Equivalence a # mappend :: Equivalence a -> Equivalence a -> Equivalence a # mconcat :: [Equivalence a] -> Equivalence a #
Monoid (Predicate a)	`mempty` on predicates always returns `True`. Without newtypes this equals `pure True`. mempty :: Predicate a mempty = _ -> True
Instance details Defined in Data.Functor.Contravariant Methods mempty :: Predicate a # mappend :: Predicate a -> Predicate a -> Predicate a # mconcat :: [Predicate a] -> Predicate a #
Monoid a => Monoid (Identity a)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Identity Methods mempty :: Identity a # mappend :: Identity a -> Identity a -> Identity a # mconcat :: [Identity a] -> Identity a #
Monoid (First a)	Since: base-2.1
Instance details Defined in Data.Monoid Methods mempty :: First a # mappend :: First a -> First a -> First a # mconcat :: [First a] -> First a #
Monoid (Last a)	Since: base-2.1
Instance details Defined in Data.Monoid Methods mempty :: Last a # mappend :: Last a -> Last a -> Last a # mconcat :: [Last a] -> Last a #
Monoid a => Monoid (Down a)	Since: base-4.11.0.0
Instance details Defined in Data.Ord Methods mempty :: Down a # mappend :: Down a -> Down a -> Down a # mconcat :: [Down a] -> Down a #
(Ord a, Bounded a) => Monoid (Max a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods mempty :: Max a # mappend :: Max a -> Max a -> Max a # mconcat :: [Max a] -> Max a #
(Ord a, Bounded a) => Monoid (Min a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods mempty :: Min a # mappend :: Min a -> Min a -> Min a # mconcat :: [Min a] -> Min a #
Monoid m => Monoid (WrappedMonoid m)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods mempty :: WrappedMonoid m # mappend :: WrappedMonoid m -> WrappedMonoid m -> WrappedMonoid m # mconcat :: [WrappedMonoid m] -> WrappedMonoid m #
Monoid a => Monoid (STM a)	Since: base-4.17.0.0
Instance details Defined in GHC.Conc.Sync Methods mempty :: STM a # mappend :: STM a -> STM a -> STM a # mconcat :: [STM a] -> STM a #
(Generic a, Monoid (Rep a ())) => Monoid (Generically a)	Since: base-4.17.0.0
Instance details Defined in GHC.Generics Methods mempty :: Generically a # mappend :: Generically a -> Generically a -> Generically a # mconcat :: [Generically a] -> Generically a #
Monoid p => Monoid (Par1 p)	Since: base-4.12.0.0
Instance details Defined in GHC.Generics Methods mempty :: Par1 p # mappend :: Par1 p -> Par1 p -> Par1 p # mconcat :: [Par1 p] -> Par1 p #
Num a => Monoid (Money a)
Instance details Defined in Data.Money Methods mempty :: Money a # mappend :: Money a -> Money a -> Money a # mconcat :: [Money a] -> Money a #
Monoid a => Monoid (IO a)	Since: base-4.9.0.0
Instance details Defined in GHC.Base Methods mempty :: IO a # mappend :: IO a -> IO a -> IO a # mconcat :: [IO a] -> IO a #
Semigroup a => Monoid (Maybe a)	Lift a semigroup into `Maybe` forming a `Monoid` according to http://en.wikipedia.org/wiki/Monoid: "Any semigroup `S` may be turned into a monoid simply by adjoining an element `e` not in `S` and defining `ee = e` and `es = s = se` for all `s ∈ S`." Since 4.11.0: constraint on inner `a` value generalised from `Monoid` to `Semigroup`. Since: base-2.1*
Instance details Defined in GHC.Base Methods mempty :: Maybe a # mappend :: Maybe a -> Maybe a -> Maybe a # mconcat :: [Maybe a] -> Maybe a #
Monoid a => Monoid (Solo a)	Since: base-4.15
Instance details Defined in GHC.Base Methods mempty :: Solo a # mappend :: Solo a -> Solo a -> Solo a # mconcat :: [Solo a] -> Solo a #
Monoid [a]	Since: base-2.1
Instance details Defined in GHC.Base Methods mempty :: [a] # mappend :: [a] -> [a] -> [a] # mconcat :: [[a]] -> [a] #
Monoid a => Monoid (Op a b)	`mempty @(Op a b)` without newtypes is `mempty @(b->a)` = `_ -> mempty`. mempty :: Op a b mempty = Op _ -> mempty
Instance details Defined in Data.Functor.Contravariant Methods mempty :: Op a b # mappend :: Op a b -> Op a b -> Op a b # mconcat :: [Op a b] -> Op a b #
Monoid (Proxy s)	Since: base-4.7.0.0
Instance details Defined in Data.Proxy Methods mempty :: Proxy s # mappend :: Proxy s -> Proxy s -> Proxy s # mconcat :: [Proxy s] -> Proxy s #
Monoid (U1 p)	Since: base-4.12.0.0
Instance details Defined in GHC.Generics Methods mempty :: U1 p # mappend :: U1 p -> U1 p -> U1 p # mconcat :: [U1 p] -> U1 p #
Monoid a => Monoid (ST s a)	Since: base-4.11.0.0
Instance details Defined in GHC.ST Methods mempty :: ST s a # mappend :: ST s a -> ST s a -> ST s a # mconcat :: [ST s a] -> ST s a #
Monoid b => Monoid (Tax a b) Source #
Instance details Defined in Data.Tax Methods mempty :: Tax a b # mappend :: Tax a b -> Tax a b -> Tax a b # mconcat :: [Tax a b] -> Tax a b #
(Monoid a, Monoid b) => Monoid (a, b)	Since: base-2.1
Instance details Defined in GHC.Base Methods mempty :: (a, b) # mappend :: (a, b) -> (a, b) -> (a, b) # mconcat :: [(a, b)] -> (a, b) #
Monoid b => Monoid (a -> b)	Since: base-2.1
Instance details Defined in GHC.Base Methods mempty :: a -> b # mappend :: (a -> b) -> (a -> b) -> a -> b # mconcat :: [a -> b] -> a -> b #
Monoid a => Monoid (Const a b)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Const Methods mempty :: Const a b # mappend :: Const a b -> Const a b -> Const a b # mconcat :: [Const a b] -> Const a b #
(Applicative f, Monoid a) => Monoid (Ap f a)	Since: base-4.12.0.0
Instance details Defined in Data.Monoid Methods mempty :: Ap f a # mappend :: Ap f a -> Ap f a -> Ap f a # mconcat :: [Ap f a] -> Ap f a #
Monoid (f p) => Monoid (Rec1 f p)	Since: base-4.12.0.0
Instance details Defined in GHC.Generics Methods mempty :: Rec1 f p # mappend :: Rec1 f p -> Rec1 f p -> Rec1 f p # mconcat :: [Rec1 f p] -> Rec1 f p #
(Profunctor p, Arrow p, Semigroup b, Monoid b) => Monoid (Closure p a b)
Instance details Defined in Data.Profunctor.Closed Methods mempty :: Closure p a b # mappend :: Closure p a b -> Closure p a b -> Closure p a b # mconcat :: [Closure p a b] -> Closure p a b #
ArrowPlus p => Monoid (Tambara p a b)
Instance details Defined in Data.Profunctor.Strong Methods mempty :: Tambara p a b # mappend :: Tambara p a b -> Tambara p a b -> Tambara p a b # mconcat :: [Tambara p a b] -> Tambara p a b #
(Monoid a, Monoid b, Monoid c) => Monoid (a, b, c)	Since: base-2.1
Instance details Defined in GHC.Base Methods mempty :: (a, b, c) # mappend :: (a, b, c) -> (a, b, c) -> (a, b, c) # mconcat :: [(a, b, c)] -> (a, b, c) #
(Monoid (f a), Monoid (g a)) => Monoid (Product f g a)	Since: base-4.16.0.0
Instance details Defined in Data.Functor.Product Methods mempty :: Product f g a # mappend :: Product f g a -> Product f g a -> Product f g a # mconcat :: [Product f g a] -> Product f g a #
(Monoid (f p), Monoid (g p)) => Monoid ((f :*: g) p)	Since: base-4.12.0.0
Instance details Defined in GHC.Generics Methods mempty :: (f :: g) p # mappend :: (f :: g) p -> (f :: g) p -> (f :: g) p # mconcat :: [(f :: g) p] -> (f :: g) p #
Monoid c => Monoid (K1 i c p)	Since: base-4.12.0.0
Instance details Defined in GHC.Generics Methods mempty :: K1 i c p # mappend :: K1 i c p -> K1 i c p -> K1 i c p # mconcat :: [K1 i c p] -> K1 i c p #
Monoid r => Monoid (Forget r a b)	Via `Monoid r => (a -> r)` Since: profunctors-5.6.2
Instance details Defined in Data.Profunctor.Types Methods mempty :: Forget r a b # mappend :: Forget r a b -> Forget r a b -> Forget r a b # mconcat :: [Forget r a b] -> Forget r a b #
(Monoid a, Monoid b, Monoid c, Monoid d) => Monoid (a, b, c, d)	Since: base-2.1
Instance details Defined in GHC.Base Methods mempty :: (a, b, c, d) # mappend :: (a, b, c, d) -> (a, b, c, d) -> (a, b, c, d) # mconcat :: [(a, b, c, d)] -> (a, b, c, d) #
Monoid (f (g a)) => Monoid (Compose f g a)	Since: base-4.16.0.0
Instance details Defined in Data.Functor.Compose Methods mempty :: Compose f g a # mappend :: Compose f g a -> Compose f g a -> Compose f g a # mconcat :: [Compose f g a] -> Compose f g a #
Monoid (f (g p)) => Monoid ((f :.: g) p)	Since: base-4.12.0.0
Instance details Defined in GHC.Generics Methods mempty :: (f :.: g) p # mappend :: (f :.: g) p -> (f :.: g) p -> (f :.: g) p # mconcat :: [(f :.: g) p] -> (f :.: g) p #
Monoid (f p) => Monoid (M1 i c f p)	Since: base-4.12.0.0
Instance details Defined in GHC.Generics Methods mempty :: M1 i c f p # mappend :: M1 i c f p -> M1 i c f p -> M1 i c f p # mconcat :: [M1 i c f p] -> M1 i c f p #
(Monoid a, Monoid b, Monoid c, Monoid d, Monoid e) => Monoid (a, b, c, d, e)	Since: base-2.1
Instance details Defined in GHC.Base Methods mempty :: (a, b, c, d, e) # mappend :: (a, b, c, d, e) -> (a, b, c, d, e) -> (a, b, c, d, e) # mconcat :: [(a, b, c, d, e)] -> (a, b, c, d, e) #

class Profunctor (p :: Type -> Type -> Type) where #

Formally, the class Profunctor represents a profunctor from Hask -> Hask.

Intuitively it is a bifunctor where the first argument is contravariant and the second argument is covariant.

You can define a Profunctor by either defining dimap or by defining both lmap and rmap.

If you supply dimap, you should ensure that:

dimap id id ≡ id

If you supply lmap and rmap, ensure:

lmap id ≡ id
rmap id ≡ id

If you supply both, you should also ensure:

dimap f g ≡ lmap f . rmap g

These ensure by parametricity:

dimap (f . g) (h . i) ≡ dimap g h . dimap f i
lmap (f . g) ≡ lmap g . lmap f
rmap (f . g) ≡ rmap f . rmap g

Minimal complete definition

dimap | lmap, rmap

Methods

dimap :: (a -> b) -> (c -> d) -> p b c -> p a d #

Map over both arguments at the same time.

dimap f g ≡ lmap f . rmap g

lmap :: (a -> b) -> p b c -> p a c #

Map the first argument contravariantly.

lmap f ≡ dimap f id

rmap :: (b -> c) -> p a b -> p a c #

Map the second argument covariantly.

rmap ≡ dimap id

Instances

Instances details

Profunctor Tax Source #
Instance details Defined in Data.Tax Methods dimap :: (a -> b) -> (c -> d) -> Tax b c -> Tax a d # lmap :: (a -> b) -> Tax b c -> Tax a c # rmap :: (b -> c) -> Tax a b -> Tax a c # (#.) :: forall a b c q. Coercible c b => q b c -> Tax a b -> Tax a c # (.#) :: forall a b c q. Coercible b a => Tax b c -> q a b -> Tax a c #
Monad m => Profunctor (Kleisli m)
Instance details Defined in Data.Profunctor.Unsafe Methods dimap :: (a -> b) -> (c -> d) -> Kleisli m b c -> Kleisli m a d # lmap :: (a -> b) -> Kleisli m b c -> Kleisli m a c # rmap :: (b -> c) -> Kleisli m a b -> Kleisli m a c # (#.) :: forall a b c q. Coercible c b => q b c -> Kleisli m a b -> Kleisli m a c # (.#) :: forall a b c q. Coercible b a => Kleisli m b c -> q a b -> Kleisli m a c #
Profunctor (CopastroSum p)
Instance details Defined in Data.Profunctor.Choice Methods dimap :: (a -> b) -> (c -> d) -> CopastroSum p b c -> CopastroSum p a d # lmap :: (a -> b) -> CopastroSum p b c -> CopastroSum p a c # rmap :: (b -> c) -> CopastroSum p a b -> CopastroSum p a c # (#.) :: forall a b c q. Coercible c b => q b c -> CopastroSum p a b -> CopastroSum p a c # (.#) :: forall a b c q. Coercible b a => CopastroSum p b c -> q a b -> CopastroSum p a c #
Profunctor (CotambaraSum p)
Instance details Defined in Data.Profunctor.Choice Methods dimap :: (a -> b) -> (c -> d) -> CotambaraSum p b c -> CotambaraSum p a d # lmap :: (a -> b) -> CotambaraSum p b c -> CotambaraSum p a c # rmap :: (b -> c) -> CotambaraSum p a b -> CotambaraSum p a c # (#.) :: forall a b c q. Coercible c b => q b c -> CotambaraSum p a b -> CotambaraSum p a c # (.#) :: forall a b c q. Coercible b a => CotambaraSum p b c -> q a b -> CotambaraSum p a c #
Profunctor (PastroSum p)
Instance details Defined in Data.Profunctor.Choice Methods dimap :: (a -> b) -> (c -> d) -> PastroSum p b c -> PastroSum p a d # lmap :: (a -> b) -> PastroSum p b c -> PastroSum p a c # rmap :: (b -> c) -> PastroSum p a b -> PastroSum p a c # (#.) :: forall a b c q. Coercible c b => q b c -> PastroSum p a b -> PastroSum p a c # (.#) :: forall a b c q. Coercible b a => PastroSum p b c -> q a b -> PastroSum p a c #
Profunctor p => Profunctor (TambaraSum p)
Instance details Defined in Data.Profunctor.Choice Methods dimap :: (a -> b) -> (c -> d) -> TambaraSum p b c -> TambaraSum p a d # lmap :: (a -> b) -> TambaraSum p b c -> TambaraSum p a c # rmap :: (b -> c) -> TambaraSum p a b -> TambaraSum p a c # (#.) :: forall a b c q. Coercible c b => q b c -> TambaraSum p a b -> TambaraSum p a c # (.#) :: forall a b c q. Coercible b a => TambaraSum p b c -> q a b -> TambaraSum p a c #
Profunctor p => Profunctor (Closure p)
Instance details Defined in Data.Profunctor.Closed Methods dimap :: (a -> b) -> (c -> d) -> Closure p b c -> Closure p a d # lmap :: (a -> b) -> Closure p b c -> Closure p a c # rmap :: (b -> c) -> Closure p a b -> Closure p a c # (#.) :: forall a b c q. Coercible c b => q b c -> Closure p a b -> Closure p a c # (.#) :: forall a b c q. Coercible b a => Closure p b c -> q a b -> Closure p a c #
Profunctor (Environment p)
Instance details Defined in Data.Profunctor.Closed Methods dimap :: (a -> b) -> (c -> d) -> Environment p b c -> Environment p a d # lmap :: (a -> b) -> Environment p b c -> Environment p a c # rmap :: (b -> c) -> Environment p a b -> Environment p a c # (#.) :: forall a b c q. Coercible c b => q b c -> Environment p a b -> Environment p a c # (.#) :: forall a b c q. Coercible b a => Environment p b c -> q a b -> Environment p a c #
Profunctor p => Profunctor (CofreeMapping p)
Instance details Defined in Data.Profunctor.Mapping Methods dimap :: (a -> b) -> (c -> d) -> CofreeMapping p b c -> CofreeMapping p a d # lmap :: (a -> b) -> CofreeMapping p b c -> CofreeMapping p a c # rmap :: (b -> c) -> CofreeMapping p a b -> CofreeMapping p a c # (#.) :: forall a b c q. Coercible c b => q b c -> CofreeMapping p a b -> CofreeMapping p a c # (.#) :: forall a b c q. Coercible b a => CofreeMapping p b c -> q a b -> CofreeMapping p a c #
Profunctor (FreeMapping p)
Instance details Defined in Data.Profunctor.Mapping Methods dimap :: (a -> b) -> (c -> d) -> FreeMapping p b c -> FreeMapping p a d # lmap :: (a -> b) -> FreeMapping p b c -> FreeMapping p a c # rmap :: (b -> c) -> FreeMapping p a b -> FreeMapping p a c # (#.) :: forall a b c q. Coercible c b => q b c -> FreeMapping p a b -> FreeMapping p a c # (.#) :: forall a b c q. Coercible b a => FreeMapping p b c -> q a b -> FreeMapping p a c #
Profunctor (Copastro p)
Instance details Defined in Data.Profunctor.Strong Methods dimap :: (a -> b) -> (c -> d) -> Copastro p b c -> Copastro p a d # lmap :: (a -> b) -> Copastro p b c -> Copastro p a c # rmap :: (b -> c) -> Copastro p a b -> Copastro p a c # (#.) :: forall a b c q. Coercible c b => q b c -> Copastro p a b -> Copastro p a c # (.#) :: forall a b c q. Coercible b a => Copastro p b c -> q a b -> Copastro p a c #
Profunctor (Cotambara p)
Instance details Defined in Data.Profunctor.Strong Methods dimap :: (a -> b) -> (c -> d) -> Cotambara p b c -> Cotambara p a d # lmap :: (a -> b) -> Cotambara p b c -> Cotambara p a c # rmap :: (b -> c) -> Cotambara p a b -> Cotambara p a c # (#.) :: forall a b c q. Coercible c b => q b c -> Cotambara p a b -> Cotambara p a c # (.#) :: forall a b c q. Coercible b a => Cotambara p b c -> q a b -> Cotambara p a c #
Profunctor (Pastro p)
Instance details Defined in Data.Profunctor.Strong Methods dimap :: (a -> b) -> (c -> d) -> Pastro p b c -> Pastro p a d # lmap :: (a -> b) -> Pastro p b c -> Pastro p a c # rmap :: (b -> c) -> Pastro p a b -> Pastro p a c # (#.) :: forall a b c q. Coercible c b => q b c -> Pastro p a b -> Pastro p a c # (.#) :: forall a b c q. Coercible b a => Pastro p b c -> q a b -> Pastro p a c #
Profunctor p => Profunctor (Tambara p)
Instance details Defined in Data.Profunctor.Strong Methods dimap :: (a -> b) -> (c -> d) -> Tambara p b c -> Tambara p a d # lmap :: (a -> b) -> Tambara p b c -> Tambara p a c # rmap :: (b -> c) -> Tambara p a b -> Tambara p a c # (#.) :: forall a b c q. Coercible c b => q b c -> Tambara p a b -> Tambara p a c # (.#) :: forall a b c q. Coercible b a => Tambara p b c -> q a b -> Tambara p a c #
Profunctor (Baz t)
Instance details Defined in Data.Profunctor.Traversing Methods dimap :: (a -> b) -> (c -> d) -> Baz t b c -> Baz t a d # lmap :: (a -> b) -> Baz t b c -> Baz t a c # rmap :: (b -> c) -> Baz t a b -> Baz t a c # (#.) :: forall a b c q. Coercible c b => q b c -> Baz t a b -> Baz t a c # (.#) :: forall a b c q. Coercible b a => Baz t b c -> q a b -> Baz t a c #
Profunctor (Bazaar a)
Instance details Defined in Data.Profunctor.Traversing Methods dimap :: (a0 -> b) -> (c -> d) -> Bazaar a b c -> Bazaar a a0 d # lmap :: (a0 -> b) -> Bazaar a b c -> Bazaar a a0 c # rmap :: (b -> c) -> Bazaar a a0 b -> Bazaar a a0 c # (#.) :: forall a0 b c q. Coercible c b => q b c -> Bazaar a a0 b -> Bazaar a a0 c # (.#) :: forall a0 b c q. Coercible b a0 => Bazaar a b c -> q a0 b -> Bazaar a a0 c #
Profunctor p => Profunctor (CofreeTraversing p)
Instance details Defined in Data.Profunctor.Traversing Methods dimap :: (a -> b) -> (c -> d) -> CofreeTraversing p b c -> CofreeTraversing p a d # lmap :: (a -> b) -> CofreeTraversing p b c -> CofreeTraversing p a c # rmap :: (b -> c) -> CofreeTraversing p a b -> CofreeTraversing p a c # (#.) :: forall a b c q. Coercible c b => q b c -> CofreeTraversing p a b -> CofreeTraversing p a c # (.#) :: forall a b c q. Coercible b a => CofreeTraversing p b c -> q a b -> CofreeTraversing p a c #
Profunctor (FreeTraversing p)
Instance details Defined in Data.Profunctor.Traversing Methods dimap :: (a -> b) -> (c -> d) -> FreeTraversing p b c -> FreeTraversing p a d # lmap :: (a -> b) -> FreeTraversing p b c -> FreeTraversing p a c # rmap :: (b -> c) -> FreeTraversing p a b -> FreeTraversing p a c # (#.) :: forall a b c q. Coercible c b => q b c -> FreeTraversing p a b -> FreeTraversing p a c # (.#) :: forall a b c q. Coercible b a => FreeTraversing p b c -> q a b -> FreeTraversing p a c #
Profunctor (Coyoneda p)
Instance details Defined in Data.Profunctor.Yoneda Methods dimap :: (a -> b) -> (c -> d) -> Coyoneda p b c -> Coyoneda p a d # lmap :: (a -> b) -> Coyoneda p b c -> Coyoneda p a c # rmap :: (b -> c) -> Coyoneda p a b -> Coyoneda p a c # (#.) :: forall a b c q. Coercible c b => q b c -> Coyoneda p a b -> Coyoneda p a c # (.#) :: forall a b c q. Coercible b a => Coyoneda p b c -> q a b -> Coyoneda p a c #
Profunctor (Yoneda p)
Instance details Defined in Data.Profunctor.Yoneda Methods dimap :: (a -> b) -> (c -> d) -> Yoneda p b c -> Yoneda p a d # lmap :: (a -> b) -> Yoneda p b c -> Yoneda p a c # rmap :: (b -> c) -> Yoneda p a b -> Yoneda p a c # (#.) :: forall a b c q. Coercible c b => q b c -> Yoneda p a b -> Yoneda p a c # (.#) :: forall a b c q. Coercible b a => Yoneda p b c -> q a b -> Yoneda p a c #
Profunctor (Tagged :: Type -> Type -> Type)
Instance details Defined in Data.Profunctor.Unsafe Methods dimap :: (a -> b) -> (c -> d) -> Tagged b c -> Tagged a d # lmap :: (a -> b) -> Tagged b c -> Tagged a c # rmap :: (b -> c) -> Tagged a b -> Tagged a c # (#.) :: forall a b c q. Coercible c b => q b c -> Tagged a b -> Tagged a c # (.#) :: forall a b c q. Coercible b a => Tagged b c -> q a b -> Tagged a c #
Functor w => Profunctor (Cokleisli w)
Instance details Defined in Data.Profunctor.Unsafe Methods dimap :: (a -> b) -> (c -> d) -> Cokleisli w b c -> Cokleisli w a d # lmap :: (a -> b) -> Cokleisli w b c -> Cokleisli w a c # rmap :: (b -> c) -> Cokleisli w a b -> Cokleisli w a c # (#.) :: forall a b c q. Coercible c b => q b c -> Cokleisli w a b -> Cokleisli w a c # (.#) :: forall a b c q. Coercible b a => Cokleisli w b c -> q a b -> Cokleisli w a c #
Functor f => Profunctor (Costar f)
Instance details Defined in Data.Profunctor.Types Methods dimap :: (a -> b) -> (c -> d) -> Costar f b c -> Costar f a d # lmap :: (a -> b) -> Costar f b c -> Costar f a c # rmap :: (b -> c) -> Costar f a b -> Costar f a c # (#.) :: forall a b c q. Coercible c b => q b c -> Costar f a b -> Costar f a c # (.#) :: forall a b c q. Coercible b a => Costar f b c -> q a b -> Costar f a c #
Profunctor (Forget r :: Type -> Type -> Type)
Instance details Defined in Data.Profunctor.Types Methods dimap :: (a -> b) -> (c -> d) -> Forget r b c -> Forget r a d # lmap :: (a -> b) -> Forget r b c -> Forget r a c # rmap :: (b -> c) -> Forget r a b -> Forget r a c # (#.) :: forall a b c q. Coercible c b => q b c -> Forget r a b -> Forget r a c # (.#) :: forall a b c q. Coercible b a => Forget r b c -> q a b -> Forget r a c #
Functor f => Profunctor (Star f)
Instance details Defined in Data.Profunctor.Types Methods dimap :: (a -> b) -> (c -> d) -> Star f b c -> Star f a d # lmap :: (a -> b) -> Star f b c -> Star f a c # rmap :: (b -> c) -> Star f a b -> Star f a c # (#.) :: forall a b c q. Coercible c b => q b c -> Star f a b -> Star f a c # (.#) :: forall a b c q. Coercible b a => Star f b c -> q a b -> Star f a c #
Profunctor (->)
Instance details Defined in Data.Profunctor.Unsafe Methods dimap :: (a -> b) -> (c -> d) -> (b -> c) -> a -> d # lmap :: (a -> b) -> (b -> c) -> a -> c # rmap :: (b -> c) -> (a -> b) -> a -> c # (#.) :: forall a b c q. Coercible c b => q b c -> (a -> b) -> a -> c # (.#) :: forall a b c q. Coercible b a => (b -> c) -> q a b -> a -> c #
Contravariant f => Profunctor (Clown f :: Type -> Type -> Type)
Instance details Defined in Data.Profunctor.Unsafe Methods dimap :: (a -> b) -> (c -> d) -> Clown f b c -> Clown f a d # lmap :: (a -> b) -> Clown f b c -> Clown f a c # rmap :: (b -> c) -> Clown f a b -> Clown f a c # (#.) :: forall a b c q. Coercible c b => q b c -> Clown f a b -> Clown f a c # (.#) :: forall a b c q. Coercible b a => Clown f b c -> q a b -> Clown f a c #
Functor f => Profunctor (Joker f :: Type -> Type -> Type)
Instance details Defined in Data.Profunctor.Unsafe Methods dimap :: (a -> b) -> (c -> d) -> Joker f b c -> Joker f a d # lmap :: (a -> b) -> Joker f b c -> Joker f a c # rmap :: (b -> c) -> Joker f a b -> Joker f a c # (#.) :: forall a b c q. Coercible c b => q b c -> Joker f a b -> Joker f a c # (.#) :: forall a b c q. Coercible b a => Joker f b c -> q a b -> Joker f a c #
Profunctor p => Profunctor (Codensity p)
Instance details Defined in Data.Profunctor.Ran Methods dimap :: (a -> b) -> (c -> d) -> Codensity p b c -> Codensity p a d # lmap :: (a -> b) -> Codensity p b c -> Codensity p a c # rmap :: (b -> c) -> Codensity p a b -> Codensity p a c # (#.) :: forall a b c q. Coercible c b => q b c -> Codensity p a b -> Codensity p a c # (.#) :: forall a b c q. Coercible b a => Codensity p b c -> q a b -> Codensity p a c #
Arrow p => Profunctor (WrappedArrow p)
Instance details Defined in Data.Profunctor.Types Methods dimap :: (a -> b) -> (c -> d) -> WrappedArrow p b c -> WrappedArrow p a d # lmap :: (a -> b) -> WrappedArrow p b c -> WrappedArrow p a c # rmap :: (b -> c) -> WrappedArrow p a b -> WrappedArrow p a c # (#.) :: forall a b c q. Coercible c b => q b c -> WrappedArrow p a b -> WrappedArrow p a c # (.#) :: forall a b c q. Coercible b a => WrappedArrow p b c -> q a b -> WrappedArrow p a c #
(Profunctor p, Profunctor q) => Profunctor (Product p q)
Instance details Defined in Data.Profunctor.Unsafe Methods dimap :: (a -> b) -> (c -> d) -> Product p q b c -> Product p q a d # lmap :: (a -> b) -> Product p q b c -> Product p q a c # rmap :: (b -> c) -> Product p q a b -> Product p q a c # (#.) :: forall a b c q0. Coercible c b => q0 b c -> Product p q a b -> Product p q a c # (.#) :: forall a b c q0. Coercible b a => Product p q b c -> q0 a b -> Product p q a c #
(Profunctor p, Profunctor q) => Profunctor (Sum p q)
Instance details Defined in Data.Profunctor.Unsafe Methods dimap :: (a -> b) -> (c -> d) -> Sum p q b c -> Sum p q a d # lmap :: (a -> b) -> Sum p q b c -> Sum p q a c # rmap :: (b -> c) -> Sum p q a b -> Sum p q a c # (#.) :: forall a b c q0. Coercible c b => q0 b c -> Sum p q a b -> Sum p q a c # (.#) :: forall a b c q0. Coercible b a => Sum p q b c -> q0 a b -> Sum p q a c #
(Functor f, Profunctor p) => Profunctor (Tannen f p)
Instance details Defined in Data.Profunctor.Unsafe Methods dimap :: (a -> b) -> (c -> d) -> Tannen f p b c -> Tannen f p a d # lmap :: (a -> b) -> Tannen f p b c -> Tannen f p a c # rmap :: (b -> c) -> Tannen f p a b -> Tannen f p a c # (#.) :: forall a b c q. Coercible c b => q b c -> Tannen f p a b -> Tannen f p a c # (.#) :: forall a b c q. Coercible b a => Tannen f p b c -> q a b -> Tannen f p a c #
(Functor f, Profunctor p) => Profunctor (Cayley f p)
Instance details Defined in Data.Profunctor.Cayley Methods dimap :: (a -> b) -> (c -> d) -> Cayley f p b c -> Cayley f p a d # lmap :: (a -> b) -> Cayley f p b c -> Cayley f p a c # rmap :: (b -> c) -> Cayley f p a b -> Cayley f p a c # (#.) :: forall a b c q. Coercible c b => q b c -> Cayley f p a b -> Cayley f p a c # (.#) :: forall a b c q. Coercible b a => Cayley f p b c -> q a b -> Cayley f p a c #
(Profunctor p, Profunctor q) => Profunctor (Procompose p q)
Instance details Defined in Data.Profunctor.Composition Methods dimap :: (a -> b) -> (c -> d) -> Procompose p q b c -> Procompose p q a d # lmap :: (a -> b) -> Procompose p q b c -> Procompose p q a c # rmap :: (b -> c) -> Procompose p q a b -> Procompose p q a c # (#.) :: forall a b c q0. Coercible c b => q0 b c -> Procompose p q a b -> Procompose p q a c # (.#) :: forall a b c q0. Coercible b a => Procompose p q b c -> q0 a b -> Procompose p q a c #
(Profunctor p, Profunctor q) => Profunctor (Rift p q)
Instance details Defined in Data.Profunctor.Composition Methods dimap :: (a -> b) -> (c -> d) -> Rift p q b c -> Rift p q a d # lmap :: (a -> b) -> Rift p q b c -> Rift p q a c # rmap :: (b -> c) -> Rift p q a b -> Rift p q a c # (#.) :: forall a b c q0. Coercible c b => q0 b c -> Rift p q a b -> Rift p q a c # (.#) :: forall a b c q0. Coercible b a => Rift p q b c -> q0 a b -> Rift p q a c #
(Profunctor p, Profunctor q) => Profunctor (Ran p q)
Instance details Defined in Data.Profunctor.Ran Methods dimap :: (a -> b) -> (c -> d) -> Ran p q b c -> Ran p q a d # lmap :: (a -> b) -> Ran p q b c -> Ran p q a c # rmap :: (b -> c) -> Ran p q a b -> Ran p q a c # (#.) :: forall a b c q0. Coercible c b => q0 b c -> Ran p q a b -> Ran p q a c # (.#) :: forall a b c q0. Coercible b a => Ran p q b c -> q0 a b -> Ran p q a c #
(Profunctor p, Functor f, Functor g) => Profunctor (Biff p f g)
Instance details Defined in Data.Profunctor.Unsafe Methods dimap :: (a -> b) -> (c -> d) -> Biff p f g b c -> Biff p f g a d # lmap :: (a -> b) -> Biff p f g b c -> Biff p f g a c # rmap :: (b -> c) -> Biff p f g a b -> Biff p f g a c # (#.) :: forall a b c q. Coercible c b => q b c -> Biff p f g a b -> Biff p f g a c # (.#) :: forall a b c q. Coercible b a => Biff p f g b c -> q a b -> Biff p f g a c #