Modulegeneric-lens-2.2.2.0Haskell2010

Data.Generics.Sum.Any

Derive a variety of prisms generically.

1 class

Packagegeneric-lens-2.2.2.0
Exports1
LanguageHaskell2010
LicenceBSD-3-Clause
SourceAny.hs

Prisms

1 declaration

Running example:

Example6 expressions

>>> :set -XTypeApplications>>> :set -XDataKinds>>> :set -XDeriveGeneric>>> import GHC.Generics>>> import Control.Lens>>> :{data Animal  = Dog Dog  | Cat Name Age  | Duck Age  deriving (Generic, Show)data Dog  = MkDog  { name :: Name  , age  :: Age  }  deriving (Generic, Show)type Name = Stringtype Age  = Intdog, cat, duck :: Animaldog = Dog (MkDog "Shep" 3)cat = Cat "Mog" 5duck = Duck 2:}

classclass AsAny (sel :: k) a s | s sel -> a where

Sums that have generic prisms.

Methods

_As :: Prism s s a a
A prism that projects a sum as identified by some selector. Currently supported selectors are constructor names and unique types. Compatible with the lens package's Control.Lens.Prism type.
Example1 expression
```
>>> dog ^? _As @"Dog"Just (MkDog {name = "Shep", age = 3})
```
Example1 expression
```
>>> dog ^? _As @DogJust (MkDog {name = "Shep", age = 3})
```
Example1 expression
```
>>> dog ^? _As @"Cat"Nothing
```
Example1 expression
```
>>> cat ^? _As @(Name, Age)Just ("Mog",5)
```
Example1 expression
```
>>> cat ^? _As @"Cat"Just ("Mog",5)
```
Example1 expression
```
>>> _As @"Cat" # ("Garfield", 6) :: AnimalCat "Garfield" 6
```
Example1 expression
```
>>> duck ^? _As @AgeJust 2
```

Instances2AsAny

AsConstructor ctor s s a a => AsAny ctor a sDefined in generic-lens-2.2.2.0 · Data.Generics.Sum.Any
AsType a s => AsAny a a sDefined in generic-lens-2.2.2.0 · Data.Generics.Sum.Any