Data.Portray.Diff

Typeclass for pretty-printed diffs between two instances of a type.

Derive it for arbitrary sum-of-products types as follows:

    data Foo = Foo Int | Bar Bool
      deriving Generic
      deriving (Portray, Diff) via Wrapped Generic Foo

If the type of the compared values has a custom Eq instance, the equality comparison used by the Generic derived Diff instance *will differ* from the custom one implemented for the type. It will only check to make sure that the representations of the two types are the same. If you still want the diff algorithm to look into the type, you will need to implement a custom Diff instance alongside the custom Eq instance. If you don't want the diff algorithm to look inside a type, and instead use the custom Eq instance, use:

    data Foo = ...
    instance Diff Foo where diff = diffAtom

Documentation

class Diff a where

Minimal complete definition

Nothing

Methods

diff :: a -> a -> Maybe Portrayal

Returns Nothing when equal; or a Portrayal showing the differences.

default diff :: (Generic a, GDiff a (Rep a)) => a -> a -> Maybe Portrayal

Instances

Diff Bool

Defined in Data.Portray.Diff

Methods

diff :: Bool -> Bool -> Maybe Portrayal

Diff Char

Defined in Data.Portray.Diff

Methods

diff :: Char -> Char -> Maybe Portrayal

Diff Double

Defined in Data.Portray.Diff

Methods

diff :: Double -> Double -> Maybe Portrayal

Diff Float

Defined in Data.Portray.Diff

Methods

diff :: Float -> Float -> Maybe Portrayal

Diff Int

Defined in Data.Portray.Diff

Methods

diff :: Int -> Int -> Maybe Portrayal

Diff Int8

Defined in Data.Portray.Diff

Methods

diff :: Int8 -> Int8 -> Maybe Portrayal

Diff Int16

Defined in Data.Portray.Diff

Methods

diff :: Int16 -> Int16 -> Maybe Portrayal

Diff Int32

Defined in Data.Portray.Diff

Methods

diff :: Int32 -> Int32 -> Maybe Portrayal

Diff Int64

Defined in Data.Portray.Diff

Methods

diff :: Int64 -> Int64 -> Maybe Portrayal

Diff Integer

Defined in Data.Portray.Diff

Methods

diff :: Integer -> Integer -> Maybe Portrayal

Diff Word

Defined in Data.Portray.Diff

Methods

diff :: Word -> Word -> Maybe Portrayal

Diff Word8

Defined in Data.Portray.Diff

Methods

diff :: Word8 -> Word8 -> Maybe Portrayal

Diff Word16

Defined in Data.Portray.Diff

Methods

diff :: Word16 -> Word16 -> Maybe Portrayal

Diff Word32

Defined in Data.Portray.Diff

Methods

diff :: Word32 -> Word32 -> Maybe Portrayal

Diff Word64

Defined in Data.Portray.Diff

Methods

diff :: Word64 -> Word64 -> Maybe Portrayal

Diff SomeTypeRep

Defined in Data.Portray.Diff

Methods

diff :: SomeTypeRep -> SomeTypeRep -> Maybe Portrayal

Diff ()

Defined in Data.Portray.Diff

Methods

diff :: () -> () -> Maybe Portrayal

Diff Assoc

Defined in Data.Portray.Diff

Methods

diff :: Assoc -> Assoc -> Maybe Portrayal

Diff Infixity

Defined in Data.Portray.Diff

Methods

diff :: Infixity -> Infixity -> Maybe Portrayal

Diff IdentKind

Defined in Data.Portray.Diff

Methods

diff :: IdentKind -> IdentKind -> Maybe Portrayal

Diff Ident

Defined in Data.Portray.Diff

Methods

diff :: Ident -> Ident -> Maybe Portrayal

Diff Portrayal

Defined in Data.Portray.Diff

Methods

diff :: Portrayal -> Portrayal -> Maybe Portrayal

Diff Text

Defined in Data.Portray.Diff

Methods

diff :: Text -> Text -> Maybe Portrayal

(Portray a, Diff a) => Diff [a]

Diff on lists does a diff on the zip, plus special handling for the mismatched lengths.

Defined in Data.Portray.Diff

Methods

diff :: [a] -> [a] -> Maybe Portrayal

(Portray a, Diff a) => Diff (Maybe a)

Defined in Data.Portray.Diff

Methods

diff :: Maybe a -> Maybe a -> Maybe Portrayal

(Eq a, Portray a) => Diff (Ratio a)

Defined in Data.Portray.Diff

Methods

diff :: Ratio a -> Ratio a -> Maybe Portrayal

Diff a => Diff (Identity a)

Defined in Data.Portray.Diff

Methods

diff :: Identity a -> Identity a -> Maybe Portrayal

(Portray a, Diff a) => Diff (NonEmpty a)

Defined in Data.Portray.Diff

Methods

diff :: NonEmpty a -> NonEmpty a -> Maybe Portrayal

(Portray a, Diff a) => Diff (IntMap a)

Defined in Data.Portray.Diff

Methods

diff :: IntMap a -> IntMap a -> Maybe Portrayal

(Portray a, Diff a) => Diff (Seq a)

Defined in Data.Portray.Diff

Methods

diff :: Seq a -> Seq a -> Maybe Portrayal

(Portray a, Diff a) => Diff (PortrayalF a)

Defined in Data.Portray.Diff

Methods

diff :: PortrayalF a -> PortrayalF a -> Maybe Portrayal

Diff a => Diff (FactorPortrayal a)

Defined in Data.Portray.Diff

Methods

diff :: FactorPortrayal a -> FactorPortrayal a -> Maybe Portrayal

(forall a. (Portray a, Diff a) => Diff (f a), forall a. Portray a => Portray (f a)) => Diff (Fix f)

Defined in Data.Portray.Diff

Methods

diff :: Fix f -> Fix f -> Maybe Portrayal

(Eq a, Portray a) => Diff (DiffAtom a)

Defined in Data.Portray.Diff

Methods

diff :: DiffAtom a -> DiffAtom a -> Maybe Portrayal

(Portray a, Portray b, Diff a, Diff b) => Diff (Either a b)

Defined in Data.Portray.Diff

Methods

diff :: Either a b -> Either a b -> Maybe Portrayal

Diff (TypeRep a)

Defined in Data.Portray.Diff

Methods

diff :: TypeRep a -> TypeRep a -> Maybe Portrayal

(Portray a, Portray b, Diff a, Diff b) => Diff (a, b)

Defined in Data.Portray.Diff

Methods

diff :: (a, b) -> (a, b) -> Maybe Portrayal

(IsList a, Portray (Item a), Diff (Item a)) => Diff (Wrapped IsList a)

Diff as if the type were a list, via toList.

Defined in Data.Portray.Diff

Methods

diff :: Wrapped IsList a -> Wrapped IsList a -> Maybe Portrayal

(Generic a, GDiff a (Rep a)) => Diff (Wrapped Generic a)

Defined in Data.Portray.Diff

Methods

diff :: Wrapped Generic a -> Wrapped Generic a -> Maybe Portrayal

(Portray a, Portray b, Portray c, Diff a, Diff b, Diff c) => Diff (a, b, c)

Defined in Data.Portray.Diff

Methods

diff :: (a, b, c) -> (a, b, c) -> Maybe Portrayal

Diff a => Diff (Const a b)

Defined in Data.Portray.Diff

Methods

diff :: Const a b -> Const a b -> Maybe Portrayal

Diff (a :~: b)

Defined in Data.Portray.Diff

Methods

diff :: (a :~: b) -> (a :~: b) -> Maybe Portrayal

(Portray a, Portray b, Portray c, Portray d, Diff a, Diff b, Diff c, Diff d) => Diff (a, b, c, d)

Defined in Data.Portray.Diff

Methods

diff :: (a, b, c, d) -> (a, b, c, d) -> Maybe Portrayal

(Portray a, Foldable f, Diff a) => Diff (Wrapped1 Foldable f a)

Diff as if the type were a list, via toList.

Defined in Data.Portray.Diff

Methods

diff :: Wrapped1 Foldable f a -> Wrapped1 Foldable f a -> Maybe Portrayal

(Portray a, Portray b, Portray c, Portray d, Portray e, Diff a, Diff b, Diff c, Diff d, Diff e) => Diff (a, b, c, d, e)

Defined in Data.Portray.Diff

Methods

diff :: (a, b, c, d, e) -> (a, b, c, d, e) -> Maybe Portrayal

diffAtom :: (Eq a, Portray a) => a -> a -> Maybe Portrayal

Diff on an atomic type, just by using the Eq and Portray instances without using any internal structure of the type.

newtype DiffAtom a

Constructors

DiffAtom a

Instances

Eq a => Eq (DiffAtom a)

Defined in Data.Portray.Diff

Methods

(==) :: DiffAtom a -> DiffAtom a -> Bool

(/=) :: DiffAtom a -> DiffAtom a -> Bool

Portray a => Portray (DiffAtom a)

Defined in Data.Portray.Diff

Methods

portray :: DiffAtom a -> Portrayal

portrayList :: [DiffAtom a] -> Portrayal

(Eq a, Portray a) => Diff (DiffAtom a)

Defined in Data.Portray.Diff

Methods

diff :: DiffAtom a -> DiffAtom a -> Maybe Portrayal

diffVs :: Portrayal -> Portrayal -> Portrayal