Extra instances for indexed traversables in Haskell

 This package provides extra instances for type-classes in the
 indexed-traversable package.
 .
 The intention is to keep this package minimal; it provides instances that
 formerly existed in lens or optics-extra.
 .
 This package provides a library for the Haskell programming language.
 See http://www.haskell.org/ for more information on Haskell.