| Copyright | (c) Andy Gill 2001 (c) Oregon Graduate Institute of Science and Technology 2001 |
|---|---|
| License | BSD-style (see the file LICENSE) |
| Maintainer | [email protected] |
| Stability | experimental |
| Portability | portable |
| Safe Haskell | Trustworthy |
| Language | Haskell2010 |
Data.Functor.Identity
Description
The identity functor and monad.
This trivial type constructor serves two purposes:
- It can be used with functions parameterized by functor or monad classes.
- It can be used as a base monad to which a series of monad
transformers may be applied to construct a composite monad.
Most monad transformer modules include the special case of
applying the transformer to
Identity. For example,State sis an abbreviation forStateT s.Identity
Since: 4.8.0.0
- newtype Identity a = Identity {
- runIdentity :: a
Documentation
Identity functor and monad. (a non-strict monad)
Since: 4.8.0.0
Constructors
| Identity | |
Fields
| |
Instances
| Monad Identity # | Since: 4.8.0.0 |
| Functor Identity # | Since: 4.8.0.0 |
| MonadFix Identity # | Since: 4.8.0.0 |
| Applicative Identity # | Since: 4.8.0.0 |
| Foldable Identity # | Since: 4.8.0.0 |
| Traversable Identity # | |
| MonadZip Identity # | Since: 4.8.0.0 |
| Show1 Identity # | Since: 4.9.0.0 |
| Read1 Identity # | Since: 4.9.0.0 |
| Ord1 Identity # | Since: 4.9.0.0 |
| Eq1 Identity # | Since: 4.9.0.0 |
| Bounded a => Bounded (Identity a) # | |
| Enum a => Enum (Identity a) # | |
| Eq a => Eq (Identity a) # | |
| Floating a => Floating (Identity a) # | |
| Fractional a => Fractional (Identity a) # | |
| Integral a => Integral (Identity a) # | |
| Data a => Data (Identity a) # | Since: 4.9.0.0 |
| Num a => Num (Identity a) # | |
| Ord a => Ord (Identity a) # | |
| Read a => Read (Identity a) # | This instance would be equivalent to the derived instances of the
Since: 4.8.0.0 |
| Real a => Real (Identity a) # | |
| RealFloat a => RealFloat (Identity a) # | |
| RealFrac a => RealFrac (Identity a) # | |
| Show a => Show (Identity a) # | This instance would be equivalent to the derived instances of the
Since: 4.8.0.0 |
| Ix a => Ix (Identity a) # | |
| IsString a => IsString (Identity a) # | |
| Generic (Identity a) # | |
| Semigroup a => Semigroup (Identity a) # | Since: 4.9.0.0 |
| Monoid a => Monoid (Identity a) # | |
| FiniteBits a => FiniteBits (Identity a) # | |
| Bits a => Bits (Identity a) # | |
| Storable a => Storable (Identity a) # | |
| Generic1 * Identity # | |
| type Rep (Identity a) # | |
| type Rep1 * Identity # | |