examples/Examples.hs · generic-lens

git.iko.soy/generic-lens

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1{-# LANGUAGE DataKinds #-}

2{-# LANGUAGE DeriveGeneric #-}

3{-# LANGUAGE DuplicateRecordFields #-}

4{-# LANGUAGE FlexibleContexts #-}

5{-# LANGUAGE TypeApplications #-}

6{-# LANGUAGE UndecidableInstances #-}

8{-# OPTIONS_GHC -fno-warn-unused-imports #-}

10module Examples where

12import GHC.Generics

13import Data.Generics.Record

14import Data.Generics.Product

15--import Control.Lens

17data Animal = Animal

18 { name :: String

19 , age :: Int

20 , eats :: String

21 } deriving (Show, Generic)

23data Human = Human

24 { name :: String

25 , age :: Int

26 , address :: String

27 , eats :: String

28 } deriving (Show, Generic)

30data Living

31 = Animal' { name :: String, eats :: String, age :: Int }

32 | Human' { name :: String, age :: Int, address :: String, eats :: String }

33 deriving (Show, Generic)

35toby :: Human

36toby = Human { name = "Toby", age = 10, address = "London", eats = "Bread" }

38growUp :: Animal -> Animal

39growUp (Animal n a _) = Animal n (a + 10) "raw meat"

41data MyRecord = MyRecord { field1 :: Int, field2 :: String } deriving Generic

43--g :: Subtype s MyRecord => s -> String

44--g s = s ^. super @MyRecord . label @"field2"