Another great writeup on lenses I highly recommend, http://www.haskellforall.com/2013/05/program-imperatively-using-haskell.html http://www.haskellforall.com/20

Another great writeup on lenses I highly recommend, http://www.haskellforall.com/2013/05/program-imperatively-using-haskell.html http://www.haskellforall.com/2013/05/program-imperatively-us....