Access the seventeenth constructor of a sum type.
Where Control.Lens._17 is the seventeenth projection out of a product, _I17 is the seventeenth
injection into a sum.
The default implementation is the prism to the seventeenth constructor of a
Generic type, injection (Proxy :: Proxy 16).
data T = C1 | C2 | C3 | C4 | C5 | C6 | C7 | C8 | C9 | C10 | C11 | C12 | C13 | C14 | C15 | C16 | C17 Int | C18 deriving (Show, Generic)instance Injection17 T T Int IntC17 1 ^? _I17Just 1
C18 ^? _I17Nothing
_I17 # 1 :: TC17 1