base-orphans defines orphan instances that mimic instances available in later
versions of base to a wider (older) range of compilers. base-orphans does
not export anything except the orphan instances themselves and complements
base-compat.
Note that base-orphans doesn’t cover every possible instance. See the
What is not covered section for exceptions.
Usage
To use base-orphans, simply import Data.Orphans ().
What is covered
Alternative, MonadPlus, and MonadZip instances for Proxy
Alternative, Applicative, Bounded, Data, Enum, Foldable, Functor, Ix, Monad, MonadFix, MonadPlus, MonadZip, and Traversable instances for data types in GHC.Generics
Alternative, Eq, Ord, Read, Show, Foldable, and Traversable instances for ZipList
We also make an attempt to keep base-orphans building with GHC HEAD, but due
to its volatility, it may not work at any given point in time. If it doesn’t,
please report it!
Patches are welcome; add tests for new code!
Changes
Changes in 0.9.2 [2024.04.30]
Backport new instances from GHC 9.10/base-4.20:
Fractional, RealFrac, Floating, and RealFloat instances for Compose
Changes in 0.9.1 [2023.10.11]
Backport new instances from GHC 9.8/base-4.19:
Eq and Ord instances for SChar, SNat, and SSymbol
Enum, Bounded, Num, Real, and Integral instances for Compose
Changes in 0.9.0 [2023.03.05]
Adapt to recent changes to Down instances:
The Bounded instance for Down was changed in base-4.15.0.0 to swap
the values of minBound and maxBound for the underlying type. This
change has now been propagated to base-orphans.
The Enum instance for Down was removed in base-4.15.0.0, but a
different version of the instance was added back in base-4.18.0.0, where
succ and pred are swapped. We have changed the backported version of
this instance in base-orphans to match the behavior of the instance
added in base-4.18.0.0.
The Integral instance for Down was removed from base entirely in
base-4.15.0.0. We have finally removed it from base-orphans in this
release, as it actively makes it more difficult to define the
aforementioned Enum instance.
Changes in 0.8.8.1 [2023.03.05]
Fix GHC 9.4 build error that was accidentally introduced in
base-orphans-0.8.8.
Changes in 0.8.8 [2023.03.05]
Backport new instances from GHC 9.6.1/base-4.18.0.0:
Functor instances for the (,,,,) a b c d, (,,,,,) a b c d e, and
(,,,,,) a b c d e f tuple types.
Eq and Ord instances for Generically1
Changes in 0.8.7 [2022.08.11]
Backport new instances from GHC 9.2.2/base-4.16.1.0:
Backport a bugfix for the Ord1 Down instance from GHC 9.4/base-4.17 such
that it now uses reverse sort order.
Changes in 0.8.6 [2021.10.29]
Backport Eq, Ord, Bounded, Enum, and Ix instances for Solo,
introduced in GHC 9.2/base-4.16
Remove the backported Eq1 and Ord1 instances for Fixed that were
introduced in base-orphans-0.8.5. While these briefly appeared in a
release candidate version of GHC 9.2.1, they were ultimately removed from
the final 9.2.1 release. This release of base-orphans synchronizes with
that change.
Changes in 0.8.5 [2021.08.29]
Backport new instances from GHC 9.2/base-4.16
Eq1, Read1, and Show1 instances for Complex
Eq1 and Ord1 instances for Fixed
Eq{1,2}, Ord{1,2}, Show{1,2}, and Read{1,2} instances for (,,)
and (,,,)
Semigroup and Monoid instances for Data.Functor.Product and
Data.Functor.Compose
Changes in 0.8.4 [2020.12.09]
Backport the Ord instances for TyCon and TypeRep to be available on
GHC 7.0.
Changes in 0.8.3 [2020.09.30]
Backport new instances from GHC 9.0/base-4.15
MonadFix and MonadZip instances for Complex
Ix instances for tuples of size 6 through 15
Changes in 0.8.2 [2020.01.27]
Backport new instances from GHC 8.10/base-4.14
Bits, Bounded, Enum, FiniteBits, Floating, Fractional,
Integral, Ix, Real, RealFrac, RealFloat and Storable instances
for Data.Ord.Down
Functor, Applicative, Monad, Alternative, and MonadPlus instances
for Kleisli
Functor, Applicative, and Monad instances for
(,,) a b and (,,,) a b c
Data instances for WrappedArrow and WrappedMonad
Data and IsList instances for ZipList
TestEquality instance for Compose
Backport the Typeable (() :: Constraint) instance to be available on
GHC 7.8.
Changes in 0.8.1 [2019.03.25]
Ensure that the test suite passes non-negative numbers to Bits methods
that require them, such as bit, setBit, clearBit, complementBit,
and testBit.
Changes in 0.8 [2018.07.02]
Backported new instance from GHC 8.6/base-4.12
Data types in GHC.Generics:
Applicative instance for K1
Semigroup instances for U1, Par1, Rec1, K1, M1, (:*:), (:.:), and V1
Monoid instances for U1, Par1, Rec1, K1, M1, (:*:), and (:.:)
Foldable and Traversable instances for Data.Monoid.Alt
MonadFix, MonadZip, Data, Foldable, Traversable, Eq1, Ord1,
Read1, and Show1 instances for Data.Ord.Down
Changes in 0.7 [2018.03.08]
Backported new instances from GHC 8.4/base-4.11
Alternative instance for ZipList
Data instance for IntPtr and WordPtr
Num, Functor, Applicative, Monad, Semigroup, and Monoid
instances for Data.Ord.Down
MonadFail, Semigroup, and Monoid instances for strict ST
Eq1, Ord1, Read1, and Show1 instances for NonEmpty
Semigroup instances for IO, Event, and Lifetime
Backported Typeable instances for (:+:), (:*:), (:.:), M1, Rec1,
ArrowMonad, Kleisli, WrappedArrow, WrappedMonad, and Any on GHC
7.6 and earlier
Backported Data instances for (:+:), (:*:), (:.:), M1, and Rec1
on GHC 7.6 and earlier
Changes in 0.5.4
Backported Bits, FiniteBits, Floating, Fractional, Integral,
IsString, Num, Real, RealFloat, and RealFrac instances for
Identity and Const (introduced in base-4.9)
Changes in 0.5.3
Backported Alternative, MonadPlus and MonadZip instances for U1 and
Proxy, and made the Functor, Foldable, Traversable, Alternative,
and Monad instances for U1 lazier to correspond with base-4.9
Changes in 0.5.2
Backported Enum, Bounded, Ix, Functor, Applicative, Monad,
MonadFix, MonadPlus, MonadZip, Foldable, Traversable, and
Data instances for datatypes in the GHC.Generics module (introduced in
base-4.9)
Changes in 0.5.1
The Storable instances for Complex and Ratio are now exactly as lazy
as their counterparts in base (see issue
#36)
Import Control.Monad.Instances (which exports Functor and Monad
instances for (->) r, and Functor instances for (,) a and Either a)
on GHCs before 7.6. This ensures that these instances will always be in
scope, and you won’t have to import a module which is deprecated on recent
GHC releases.
Fix build on GHC HEAD (again)
Changes in 0.4.4
Fix build on GHC HEAD
Changes in 0.4.3
Fix build on OSes where HTYPE_DEV_T = Int32 (e.g., OS X)
Changes in 0.4.2
Functor instances for Handler
Functor. Applicative, Alternative, and MonadPlus instances for
ArrowMonad
Expose Read and Show instances for Down on GHCs before 7.8
Bits, Bounded, and Integral instances for CDev
Changes in 0.4.1
Fixed imports on GHC < 7.8 on Windows
Changes in 0.4.0
Removed all Generic and Generic1 instances. These have been moved to the
generic-deriving library.
Changes in 0.3.3
Typeable instances for (~), Any, Constraint, CSigset, Handler,
Opaque, SPEC, and every promotable data constructor in base
Changes in 0.3.2
Storable (Complex a) instance no longer requires a RealFloat a
constraint if using base-4.4 or later
Changes in 0.3.1
Functor, Applicative, and Monad instances for First and Last
Changes in 0.3.0
Show instance for Fingerprint
Data.Orphans is now Trustworthy
Backported the Generic and Generic1 instances available in base-4.7.0.0
to GHC 7.2, 7.4, and 7.6, namely
Const, WrappedMonad, and ZipList from Control.Applicative
WrappedArrow from Control.Category
All, Any, Dual, Endo, First, Last, Product, and Sum from
Data.Monoid
U1, Par1, Rec1, K1, M1, (:+:), (:*:), (:.:), Arity,
Associativity, and Fixity from GHC.Generics
Changes in 0.2.0
Drop GHC 6.12 (and base-4.2.0.0) compatibility
Fix Windows, GHCJS build
Read instance for Fixed
Applicative instances for strict and lazy ST
Typeable instance for SampleVar
Applicative and Alternative instances for ReadP and ReadPrec
Typeable instance for KProxy
Typeable instances for more data types in GHC.-prefixed modules
Generic instances for Arity, Associativity, and Fixity from
the GHC.Generics module
Corrected the Generic instance for (:*:) to work around GHC bug #9830
