case-insensitive string comparison

 The module Data.CaseInsensitive provides the CI type constructor which
 can be parameterised by a string-like type like: String, ByteString,
 Text, etc.. Comparisons of values of the resulting type will be
 insensitive to cases.
 .
 This package provides a library for the Haskell programming language.
 See http://www.haskell.org/ for more information on Haskell.