.
 Partial functions from the base library, such as head and !!, modified to
 return more descriptive error messages, programmer defined error messages,
 Maybe wrapped results and default values. These functions can be used to
 reduce the number of unsafe pattern matches in your code.
 .
 This package provides the documentation for a library for the Haskell
 programming language.
 See http://www.haskell.org/ for more information on Haskell.