b3a8b00..develop · patch

git.iko.soy/patch

on develop help sign in

.github/workflows/haskell.yml+1−1

since splitsnapshots

unifiedsplit

@@ -42,6 +42,6 @@ jobs:

42 - name: Build

43 run: cabal build --enable-tests --enable-benchmarks all

44 - name: Run tests

45− run: cabal test all

45+ run: cabal test --enable-tests all

46 - name: Build Docs

47 run: cabal haddock

.travis.ymldeleted−171

@@ -1,171 +0,0 @@

1−# This Travis job script has been generated by a script via

2−#

3−# haskell-ci '--config=cabal.haskell-ci' 'cabal.project'

4−#

5−# For more information, see https://github.com/haskell-CI/haskell-ci

6−#

7−# version: 0.3.20190814

8−#

9−language: c

10−dist: xenial

11−sudo: required

12−git:

13− # whether to recursively clone submodules

14− submodules: false

15−cache:

16− directories:

17− - $HOME/.cabal/packages

18− - $HOME/.cabal/store

19−before_cache:

20− - rm -fv $CABALHOME/packages/hackage.haskell.org/build-reports.log

21− # remove files that are regenerated by 'cabal update'

22− - rm -fv $CABALHOME/packages/hackage.haskell.org/00-index.*

23− - rm -fv $CABALHOME/packages/hackage.haskell.org/*.json

24− - rm -fv $CABALHOME/packages/hackage.haskell.org/01-index.cache

25− - rm -fv $CABALHOME/packages/hackage.haskell.org/01-index.tar

26− - rm -fv $CABALHOME/packages/hackage.haskell.org/01-index.tar.idx

27− - rm -rfv $CABALHOME/packages/head.hackage

28−matrix:

29− include:

30− - compiler: ghcjs-8.4

31− addons: {"apt":{"sources":["hvr-ghc"],"packages":["cabal-install-3.0"]}}

32− - compiler: ghc-8.8.1

33− addons: {"apt":{"sources":["hvr-ghc"],"packages":["ghc-8.8.1","cabal-install-3.0"]}}

34− - compiler: ghc-8.6.5

35− addons: {"apt":{"sources":["hvr-ghc"],"packages":["ghc-8.6.5","cabal-install-2.4"]}}

36− - compiler: ghc-8.4.4

37− addons: {"apt":{"sources":["hvr-ghc"],"packages":["ghc-8.4.4","cabal-install-2.4"]}}

38− - compiler: ghc-8.2.2

39− addons: {"apt":{"sources":["hvr-ghc"],"packages":["ghc-8.2.2","cabal-install-2.4"]}}

40− - compiler: ghc-8.0.2

41− addons: {"apt":{"sources":["hvr-ghc"],"packages":["ghc-8.0.2","cabal-install-2.4"]}}

42−before_install:

43− - |

44− if [ "$TRAVIS_OS_NAME" = "linux" ]; then

45− sudo add-apt-repository -y ppa:hvr/ghcjs;

46− curl -s https://deb.nodesource.com/gpgkey/nodesource.gpg.key | sudo apt-key add -

47− sudo apt-add-repository 'https://deb.nodesource.com/node_8.x xenial main'

48− sudo apt-get update;

49− sudo apt-get install $CC cabal-install-3.0 nodejs;

50− fi

51− - HC=$(echo "/opt/$CC/bin/ghc" | sed 's/-/\//')

52− - WITHCOMPILER="-w $HC"

53− - |

54− if echo $CC | grep -q ghcjs; then

55− GHCJS=true

56− HC=${HC}js

57− WITHCOMPILER="--ghcjs ${WITHCOMPILER}js"

58− else

59− GHCJS=false;

60− fi

61− - if $GHCJS ; then sudo apt-get install -y ghc-8.4.4 ; fi

62− - if $GHCJS ; then PATH="/opt/ghc/8.4.4/bin:$PATH" ; fi

63− - HCPKG="$HC-pkg"

64− - unset CC

65− - CABAL=/opt/ghc/bin/cabal

66− - CABALHOME=$HOME/.cabal

67− - export PATH="$CABALHOME/bin:$PATH"

68− - TOP=$(pwd)

69− - "HCNUMVER=$(${HC} --numeric-version|perl -ne '/^(\\d+)\\.(\\d+)\\.(\\d+)(\\.(\\d+))?$/; print(10000 * $1 + 100 * $2 + ($3 == 0 ? $5 != 1 : $3))')"

70− - echo $HCNUMVER

71− - CABAL="$CABAL -vnormal+nowrap+markoutput"

72− - set -o pipefail

73− - |

74− echo 'function blue(s) { printf "\033[0;34m" s "\033[0m " }' >> .colorful.awk

75− echo 'BEGIN { state = "output"; }' >> .colorful.awk

76− echo '/^-----BEGIN CABAL OUTPUT-----$/ { state = "cabal" }' >> .colorful.awk

77− echo '/^-----END CABAL OUTPUT-----$/ { state = "output" }' >> .colorful.awk

78− echo '!/^(-----BEGIN CABAL OUTPUT-----|-----END CABAL OUTPUT-----)/ {' >> .colorful.awk

79− echo ' if (state == "cabal") {' >> .colorful.awk

80− echo ' print blue($0)' >> .colorful.awk

81− echo ' } else {' >> .colorful.awk

82− echo ' print $0' >> .colorful.awk

83− echo ' }' >> .colorful.awk

84− echo '}' >> .colorful.awk

85− - cat .colorful.awk

86− - |

87− color_cabal_output () {

88− awk -f $TOP/.colorful.awk

89− }

90− - echo text | color_cabal_output

91−install:

92− - ${CABAL} --version

93− - echo "$(${HC} --version) [$(${HC} --print-project-git-commit-id 2> /dev/null || echo '?')]"

94− - node --version

95− - echo $GHCJS

96− - TEST=--enable-tests

97− - BENCH=--enable-benchmarks

98− - BENCH=--disable-benchmarks

99− - HEADHACKAGE=false

100− - rm -f $CABALHOME/config

101− - |

102− echo "verbose: normal +nowrap +markoutput" >> $CABALHOME/config

103− echo "remote-build-reporting: anonymous" >> $CABALHOME/config

104− echo "write-ghc-environment-files: always" >> $CABALHOME/config

105− echo "remote-repo-cache: $CABALHOME/packages" >> $CABALHOME/config

106− echo "logs-dir: $CABALHOME/logs" >> $CABALHOME/config

107− echo "world-file: $CABALHOME/world" >> $CABALHOME/config

108− echo "extra-prog-path: $CABALHOME/bin" >> $CABALHOME/config

109− echo "symlink-bindir: $CABALHOME/bin" >> $CABALHOME/config

110− echo "installdir: $CABALHOME/bin" >> $CABALHOME/config

111− echo "build-summary: $CABALHOME/logs/build.log" >> $CABALHOME/config

112− echo "store-dir: $CABALHOME/store" >> $CABALHOME/config

113− echo "install-dirs user" >> $CABALHOME/config

114− echo " prefix: $CABALHOME" >> $CABALHOME/config

115− echo "repository hackage.haskell.org" >> $CABALHOME/config

116− echo " url: http://hackage.haskell.org/" >> $CABALHOME/config

117− - cat $CABALHOME/config

118− - rm -fv cabal.project cabal.project.local cabal.project.freeze

119− - travis_retry ${CABAL} v2-update -v

120− - if $GHCJS ; then (cd /tmp && ${CABAL} v2-install -w ghc-8.4.4 happy) ; fi

121− # Generate cabal.project

122− - rm -rf cabal.project cabal.project.local cabal.project.freeze

123− - touch cabal.project

124− - |

125− echo "packages: ." >> cabal.project

126− - |

127− - cat cabal.project || true

128− - cat cabal.project.local || true

129− - if [ -f "./configure.ac" ]; then (cd "." && autoreconf -i); fi

130− - ${CABAL} v2-freeze $WITHCOMPILER ${TEST} ${BENCH} | color_cabal_output

131− - "cat cabal.project.freeze | sed -E 's/^(constraints: *| *)//' | sed 's/any.//'"

132− - rm cabal.project.freeze

133−script:

134− - DISTDIR=$(mktemp -d /tmp/dist-test.XXXX)

135− # Packaging...

136− - ${CABAL} v2-sdist all | color_cabal_output

137− # Unpacking...

138− - mv dist-newstyle/sdist/*.tar.gz ${DISTDIR}/

139− - cd ${DISTDIR} || false

140− - find . -maxdepth 1 -type f -name '*.tar.gz' -exec tar -xvf '{}' \;

141− - find . -maxdepth 1 -type f -name '*.tar.gz' -exec rm '{}' \;

142− - PKGDIR_patch="$(find . -maxdepth 1 -type d -regex '.*/patch-[0-9.]*')"

143− # Generate cabal.project

144− - rm -rf cabal.project cabal.project.local cabal.project.freeze

145− - touch cabal.project

146− - |

147− echo "packages: ${PKGDIR_patch}" >> cabal.project

148− - |

149− - cat cabal.project || true

150− - cat cabal.project.local || true

151− # Building...

152− # this builds all libraries and executables (without tests/benchmarks)

153− - ${CABAL} v2-build $WITHCOMPILER --disable-tests --disable-benchmarks all | color_cabal_output

154− # Building with tests and benchmarks...

155− # build & run tests, build benchmarks

156− - ${CABAL} v2-build $WITHCOMPILER ${TEST} ${BENCH} all | color_cabal_output

157− # Testing...

158− - if ! $GHCJS ; then ${CABAL} v2-test $WITHCOMPILER ${TEST} ${BENCH} all | color_cabal_output ; fi

159− # cabal check...

160− - (cd ${PKGDIR_patch} && ${CABAL} -vnormal check)

161− # haddock...

162− - if ! $GHCJS ; then ${CABAL} v2-haddock $WITHCOMPILER ${TEST} ${BENCH} all | color_cabal_output ; fi

163− # Constraint sets

164− - rm -rf cabal.project.local

165− # Constraint set old-these

166− - if $GHCJS || ! $GHCJS && [ $HCNUMVER -lt 80800 ] ; then ${CABAL} v2-build $WITHCOMPILER --disable-tests --disable-benchmarks --constraint='these <1' all | color_cabal_output ; fi

167− # Constraint set old-witherable

168− - ${CABAL} v2-build $WITHCOMPILER --disable-tests --disable-benchmarks --constraint='witherable <0.3.2' all | color_cabal_output

169−

170−# REGENDATA ["--config=cabal.haskell-ci","cabal.project"]

171−# EOF

ChangeLog.md+11−21

@@ -2,49 +2,39 @@

3## Unreleased

5−* Remove the `split-these` flag.

5+* New dep of `data-orphans` for old GHC to get instances honestly instead of

6− We do not need it as we only use the `These` datatype which is provided in all versions.

6+ via `monoidal-containers`.

8−* Stop defining `Group`; `Group` from the `groups` package can be used instead.

8+## 0.0.5.0 - 2021-12-17

9−

10− Most of the instances are provided by `groups`, except the `Group

11− MonoidalMap` instance, which is not lawful. `reflex` might provide it as an

12− orphan for backwards compat, temporarily, but it should eventually be removed

13− everywhere.

14−

15−* `Additive` is still defined, because the `Abelian` from `groups` has too

16− stringent a constraint.

18* `Additive` now lives in `Data.Semigroup.Additive`, but is still reexported

10* `Additive` now lives in `Data.Semigroup.Additive`, but is still reexported

19 from `Data.Patch` for compatability.

11 from `Data.Patch` for compatability.

21−## Unreleased

22−

23* Rewrite `PatchMapWithMove` in terms of `PatchMapWithPatchingMove`.

13* Rewrite `PatchMapWithMove` in terms of `PatchMapWithPatchingMove`.

24 Care is taken to make this not a breaking change.

14 Care is taken to make this not a breaking change.

25 In particular, `PatchMapWithMove` is a newtype of `PatchMapWithPatchingMove`, as is the `NodeInfo` and `From` of `PatchMapWithPatchingMove`'s versions of those.

15 In particular, `PatchMapWithMove` is a newtype of `PatchMapWithPatchingMove`, as is the `NodeInfo` and `From` of `PatchMapWithPatchingMove`'s versions of those.

26 There are complete constructor and field patterns too, and everything is

16 There are complete constructor and field patterns too, and everything is

27 exported under the newtype as real constructors and fields would be.

17 exported under the newtype as real constructors and fields would be.

29−## 0.0.4.0

19+## 0.0.4.0 - 2021-04-20

31* Enable PolyKinds

21* Enable PolyKinds

33−## 0.0.3.2

23+## 0.0.3.2 - 2020-11-06

35* Update version bounds

25* Update version bounds

37−## 0.0.3.1

27+## 0.0.3.1 - 2020-02-05

39* Replace `fromJust` with something easier to debug.

29* Replace `fromJust` with something easier to debug.

41−## 0.0.3.0

31+## 0.0.3.0 - 2020-02-05

43* Create `PatchMapWithPatchingMove` variant which supports moves with a patch.

33* Create `PatchMapWithPatchingMove` variant which supports moves with a patch.

45* Create `DecidablyEmpty` subclass of `Monoid`.

35* Create `DecidablyEmpty` subclass of `Monoid`.

47−## 0.0.2.0

37+## 0.0.2.0 - 2020-01-17

49* Consistently provide:

39* Consistently provide:

@@ -56,16 +46,16 @@

57 for `PatchMap`, `PatchIntMap`, and `PatchMapWithMove`.

47 for `PatchMap`, `PatchIntMap`, and `PatchMapWithMove`.

59−## 0.0.1.0

49+## 0.0.1.0 - 2020-01-09

61* Support older GHCs with `split-these` flag.

51* Support older GHCs with `split-these` flag.

63* Additional instances for the `Group` class for basic types.

53* Additional instances for the `Group` class for basic types.

65−## 0.0.0.1

55+## 0.0.0.1 - 2020-01-08

67* Remove unneeded dependencies

57* Remove unneeded dependencies

69−## 0.0.0.0

59+## 0.0.0.0 - 2020-01-08

71* Extract patching functionality from Reflex.

61* Extract patching functionality from Reflex.

cabal.haskell-cideleted−14

@@ -1,14 +0,0 @@

1−distribution: xenial

2−benchmarks: False

3−unconstrained: False

4−installed: -all

5−

6−-- https://github.com/haskell/cabal/issues/6106

7−install-dependencies: False

8−

9−constraint-set old-these

10− ghc: <8.8

11− constraints: these <1

12−

13−constraint-set old-witherable

14− constraints: witherable <0.3.2

dep/reflex-platform/default.nix+7−1

@@ -1,2 +1,8 @@

1# DO NOT HAND-EDIT THIS FILE

2−import (import ./thunk.nix)

2+let fetch = { private ? false, fetchSubmodules ? false, owner, repo, rev, sha256, ... }:

3+ if !fetchSubmodules && !private then builtins.fetchTarball {

4+ url = "https://github.com/${owner}/${repo}/archive/${rev}.tar.gz"; inherit sha256;

5+ } else (import <nixpkgs> {}).fetchFromGitHub {

6+ inherit owner repo rev sha256 fetchSubmodules private;

7+ };

8+in import (fetch (builtins.fromJSON (builtins.readFile ./github.json)))

dep/reflex-platform/github.json+2−2

@@ -3,6 +3,6 @@

3 "repo": "reflex-platform",

4 "branch": "master",

5 "private": false,

6− "rev": "efc6d923c633207d18bd4d8cae3e20110a377864",

6+ "rev": "c9d11db1b98855fe8ab24a3ff6a5dbe0ad902ad9",

7− "sha256": "121rmnkx8nwiy96ipfyyv6vrgysv0zpr2br46y70zf4d0y1h1lz5"

7+ "sha256": "0sfzkqdvyah5mwvmli0wq1nl0b8cvk2cmfgfy4rz57wv42x3099y"

dep/reflex-platform/thunk.nixdeleted−9

@@ -1,9 +0,0 @@

1−# DO NOT HAND-EDIT THIS FILE

2−let fetch = { private ? false, fetchSubmodules ? false, owner, repo, rev, sha256, ... }:

3− if !fetchSubmodules && !private then builtins.fetchTarball {

4− url = "https://github.com/${owner}/${repo}/archive/${rev}.tar.gz"; inherit sha256;

5− } else (import <nixpkgs> {}).fetchFromGitHub {

6− inherit owner repo rev sha256 fetchSubmodules private;

7− };

8− json = builtins.fromJSON (builtins.readFile ./github.json);

9−in fetch json

patch.cabal+15−3

@@ -1,5 +1,5 @@

1Name: patch

2−Version: 0.1.0.0

2+Version: 0.0.5.0

3Synopsis: Data structures for describing changes to other data structures.

4Description:

5 Data structures for describing changes to other data structures.

@@ -25,6 +25,11 @@ tested-with:

25 GHC ==8.0.2 || ==8.2.2 || ==8.4.4 || ==8.6.5 || ==8.8.1

26 GHCJS ==8.4

28+flag split-these

29+ description: Use split these/semialign packages

30+ manual: False

31+ default: True

32+

28library

33library

29 hs-source-dirs: src

34 hs-source-dirs: src

30 default-language: Haskell2010

35 default-language: Haskell2010

@@ -35,9 +40,8 @@ library

35 , dependent-sum >= 0.6 && < 0.8

40 , dependent-sum >= 0.6 && < 0.8

36 , lens >= 4.7 && < 5

41 , lens >= 4.7 && < 5

37 , semigroupoids >= 4.0 && < 6

42 , semigroupoids >= 4.0 && < 6

38− , these >= 0.4 && < 1.2

39 , transformers >= 0.5.6.0 && < 0.6

43 , transformers >= 0.5.6.0 && < 0.6

40− , witherable >= 0.3 && < 0.4

44+ , witherable >= 0.3 && < 0.5

42 if impl(ghc < 8.6) -- really, if base < 8.12

46 if impl(ghc < 8.6) -- really, if base < 8.12

43 build-depends: base-orphans >= 0.8 && < 0.9

47 build-depends: base-orphans >= 0.8 && < 0.9

@@ -57,6 +61,14 @@ library

57 ghc-options: -Wall -fwarn-redundant-constraints -fwarn-tabs

61 ghc-options: -Wall -fwarn-redundant-constraints -fwarn-tabs

58 default-extensions: PolyKinds

62 default-extensions: PolyKinds

64+ if flag(split-these)

65+ build-depends: these >= 1 && <1.2

66+ , semialign >=1 && <1.2

67+ , monoidal-containers >= 0.6 && < 0.7

68+ else

69+ build-depends: these >= 0.4 && <0.9

70+ , monoidal-containers == 0.4.0.0

71+

60test-suite tests

72test-suite tests

61 default-language: Haskell2010

73 default-language: Haskell2010

62 type: exitcode-stdio-1.0

74 type: exitcode-stdio-1.0

src/Data/Patch.hs+56−1

@@ -1,6 +1,8 @@

1{-# LANGUAGE CPP #-}

2−{-# LANGUAGE TypeOperators #-}

2+{-# LANGUAGE GeneralizedNewtypeDeriving #-}

3+{-# LANGUAGE StandaloneDeriving #-}

3{-# LANGUAGE TypeFamilies #-}

4{-# LANGUAGE TypeFamilies #-}

5+{-# LANGUAGE TypeOperators #-}

4-- |

6-- |

5-- Module:

7-- Module:

6-- Data.Patch

8-- Data.Patch

@@ -11,9 +13,15 @@ module Data.Patch

11 , module X

13 , module X

12 ) where

14 ) where

16+import Control.Applicative

17+import Data.Functor.Const (Const (..))

18+import Data.Functor.Identity

19+import Data.Map.Monoidal (MonoidalMap)

20+import Data.Proxy

14#if !MIN_VERSION_base(4,11,0)

21#if !MIN_VERSION_base(4,11,0)

15import Data.Semigroup (Semigroup (..))

22import Data.Semigroup (Semigroup (..))

16#endif

23#endif

24+import GHC.Generics

18import Data.Semigroup.Additive as X

26import Data.Semigroup.Additive as X

19import Data.Patch.Class as X

27import Data.Patch.Class as X

@@ -32,9 +40,56 @@ import Data.Patch.MapWithMove as X

32 , unsafePatchMapWithMove

40 , unsafePatchMapWithMove

33 )

41 )

43+-- | A 'Group' is a 'Monoid' where every element has an inverse.

44+class (Semigroup q, Monoid q) => Group q where

45+ negateG :: q -> q

46+ (~~) :: q -> q -> q

47+ r ~~ s = r <> negateG s

48+

35-- | The elements of an 'Additive' 'Semigroup' can be considered as patches of their own type.

49-- | The elements of an 'Additive' 'Semigroup' can be considered as patches of their own type.

36newtype AdditivePatch p = AdditivePatch { unAdditivePatch :: p }

50newtype AdditivePatch p = AdditivePatch { unAdditivePatch :: p }

38instance Additive p => Patch (AdditivePatch p) where

52instance Additive p => Patch (AdditivePatch p) where

39 type PatchTarget (AdditivePatch p) = p

53 type PatchTarget (AdditivePatch p) = p

40 apply (AdditivePatch p) q = Just $ p <> q

54 apply (AdditivePatch p) q = Just $ p <> q

55+

56+instance (Ord k, Group q) => Group (MonoidalMap k q) where

57+ negateG = fmap negateG

58+

59+-- | Trivial group.

60+instance Group () where

61+ negateG _ = ()

62+ _ ~~ _ = ()

63+

64+-- | Product group. A Pair of groups gives rise to a group

65+instance (Group a, Group b) => Group (a, b) where

66+ negateG (a, b) = (negateG a, negateG b)

67+ (a, b) ~~ (c, d) = (a ~~ c, b ~~ d)

68+

69+-- See https://gitlab.haskell.org/ghc/ghc/issues/11135#note_111802 for the reason Compose is not also provided.

70+-- Base does not define Monoid (Compose f g a) so this is the best we can

71+-- really do for functor composition.

72+instance Group (f (g a)) => Group ((f :.: g) a) where

73+ negateG (Comp1 xs) = Comp1 (negateG xs)

74+ Comp1 xs ~~ Comp1 ys = Comp1 (xs ~~ ys)

75+

76+-- | Product of groups, Functor style.

77+instance (Group (f a), Group (g a)) => Group ((f :*: g) a) where

78+ negateG (a :*: b) = negateG a :*: negateG b

79+ (a :*: b) ~~ (c :*: d) = (a ~~ c) :*: (b ~~ d)

80+

81+-- | Trivial group, Functor style

82+instance Group (Proxy x) where

83+ negateG _ = Proxy

84+ _ ~~ _ = Proxy

85+

86+-- | Const lifts groups into a functor.

87+deriving instance Group a => Group (Const a x)

88+

89+-- | Identity lifts groups pointwise (at only one point)

90+deriving instance Group a => Group (Identity a)

91+

92+-- | Functions lift groups pointwise.

93+instance Group b => Group (a -> b) where

94+ negateG f = negateG . f

95+ (~~) = liftA2 (~~)

src/Data/Semigroup/Additive.hs+9−7

@@ -26,10 +26,11 @@ import GHC.Generics

26-- | An 'Additive' 'Semigroup' is one where (<>) is commutative

27class Semigroup q => Additive q where

29−-- | Trivial group.

29+-- | Trivial additive semigroup.

30instance Additive ()

32−-- | Product group. A Pair of groups gives rise to a group

32+-- | Product additive semigroup.

33+-- A Pair of additive semigroups gives rise to a additive semigroup

33instance (Additive a, Additive b) => Additive (a, b)

34instance (Additive a, Additive b) => Additive (a, b)

35-- See https://gitlab.haskell.org/ghc/ghc/issues/11135#note_111802 for the reason Compose is not also provided.

36-- See https://gitlab.haskell.org/ghc/ghc/issues/11135#note_111802 for the reason Compose is not also provided.

@@ -37,16 +38,17 @@ instance (Additive a, Additive b) => Additive (a, b)

37-- really do for functor composition.

38-- really do for functor composition.

38instance Additive (f (g a)) => Additive ((f :.: g) a)

39instance Additive (f (g a)) => Additive ((f :.: g) a)

40−-- | Product of groups, Functor style.

41+-- | Product of additive semigroups, Functor style.

41instance (Additive (f a), Additive (g a)) => Additive ((f :*: g) a)

42instance (Additive (f a), Additive (g a)) => Additive ((f :*: g) a)

43−-- | Trivial group, Functor style

44+-- | Trivial additive semigroup, Functor style

44instance Additive (Proxy x)

45instance Additive (Proxy x)

46−-- | Const lifts groups into a functor.

47+-- | Const lifts additive semigroups into a functor.

47instance Additive a => Additive (Const a x)

48instance Additive a => Additive (Const a x)

49+

48−-- | Ideitnty lifts groups pointwise (at only one point)

50+-- | Identity lifts additive semigroups pointwise (at only one point)

49instance Additive a => Additive (Identity a)

51instance Additive a => Additive (Identity a)

51−-- | Functions lift groups pointwise.

53+-- | Functions lift additive semigroups pointwise.

52instance Additive b => Additive (a -> b)

54instance Additive b => Additive (a -> b)