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GHC 10.0.0.20260917 · lts/ghc-10.0.x · fc4e598 · 2026-10-11

Moduleeither-n-0.1.0.0Haskell2010

Data.Lens.Injection.Injection19

The nineteenth injection of a sum type, as a prism. The sum-type dual of Control.Lens.Field19.

  • 1 class
  • Packageeither-n-0.1.0.0
  • Exports1
  • LanguageHaskell2010
  • LicenceBSD-3-Clause
  • SourceInjection19.hs
classclass Injection19 s t a b | s -> a, t -> b, s b -> t, t a -> s where
#

Access the nineteenth constructor of a sum type.

Where Control.Lens._19 is the nineteenth projection out of a product, _I19 is the nineteenth injection into a sum.

The default implementation is the prism to the nineteenth constructor of a Generic type, injection (Proxy :: Proxy 18).

Example3 expressions
data T = C1 | C2 | C3 | C4 | C5 | C6 | C7 | C8 | C9 | C10 | C11 | C12 | C13 | C14 | C15 | C16 | C17 | C18 | C19 Int | C20 deriving (Show, Generic)instance Injection19 T T Int IntC19 1 ^? _I19Just 1
Example1 expression
C20 ^? _I19Nothing
Example1 expression
_I19 # 1 :: TC19 1

Methods