base-orphans

Scope

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

• Added Applicative and Alternative instances for ReadP and ReadPrec
• Added Bits, Bounded, and Integral instances for CDev
• Added Eq and Ord instances for Control.Exception.ErrorCall
• Added Eq, Ord, Read, and Show instances for data types in GHC.Generics
• Added Functor, Applicative, Alternative, and MonadPlus instances for ArrowMonad
• Added Functor, Applicative, and Monad instances for First and Last
• Added Monoid, Eq, Ord, Read, and Show instances for Const
• Added Read and Show instances for Down
• Added Eq, Ord, Read, and Show instances for ZipList
• Added Monad instance for WrappedMonad
• Added Data and IsList instances for Version
• Applicative instance for strict and lazy ST
• Bits instance for Bool
• Foldable instance for Either, (,) and Const
• Functor instance for Handler, ArgOrder, OptDescr, and ArgDescr
• Num instance for Sum and Product
• Read instance for Fixed
• Show instance for Fingerprint
• Storable instance for Complex and Ratio
• Traversable instance for Either, (,) and Const
• Typeable instance for most data types, typeclasses, and promoted data constructors (when possible)

What is not covered

base-orphans does not define the following instances:

• Generic or Generic1 instances. These can be found in the Generics.Deriving.Instances module of the generic-deriving library.

Supported versions of GHC/base

• ghc-7.10.2 / base-4.8.1.0
• ghc-7.10.1 / base-4.8.0.0
• ghc-7.8.4 / base-4.7.0.2
• ghc-7.8.3 / base-4.7.0.1
• ghc-7.8.2 / base-4.7.0.0
• ghc-7.8.1 / base-4.7.0.0
• ghc-7.6.3 / base-4.6.0.1
• ghc-7.6.2 / base-4.6.0.1
• ghc-7.6.1 / base-4.6.0.0
• ghc-7.4.2 / base-4.5.1.0
• ghc-7.4.1 / base-4.5.0.0
• ghc-7.2.2 / base-4.4.1.0
• ghc-7.2.1 / base-4.4.0.0
• ghc-7.0.4 / base-4.3.1.0
• ghc-7.0.3 / base-4.3.1.0
• ghc-7.0.2 / base-4.3.1.0
• ghc-7.0.1 / base-4.3.0.0

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!