title: lenses, fclabels, data-accessor - which library for structure access and mutation is better
body: <p>There are at least three popular libraries for accessing and manipulating fields of records. The ones I know of are: data-accessor, fclabels and lenses. </p>
  
  <p>Personally I started with data-accessor and I'm using them now. However recently on haskell-cafe there was an opinion of fclabels being superior.</p>
  
  <p>Therefore I'm interested in comparison of those three (and maybe more) libraries.</p>