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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.Injection9

The ninth injection of a sum type, as a prism. The sum-type dual of Control.Lens.Field9.

  • 1 class
  • Packageeither-n-0.1.0.0
  • Exports1
  • LanguageHaskell2010
  • LicenceBSD-3-Clause
  • SourceInjection9.hs
classclass Injection9 s t a b | s -> a, t -> b, s b -> t, t a -> s where
#

Access the ninth constructor of a sum type.

Where Control.Lens._9 is the ninth projection out of a product, _I9 is the ninth injection into a sum.

The default implementation is the prism to the ninth constructor of a Generic type, injection (Proxy :: Proxy 8).

Example3 expressions
data T = C1 | C2 | C3 | C4 | C5 | C6 | C7 | C8 | C9 Int | C10 deriving (Show, Generic)instance Injection9 T T Int IntC9 1 ^? _I9Just 1
Example1 expression
C10 ^? _I9Nothing
Example1 expression
_I9 # 1 :: TC9 1

Methods