Algorithms in their purely functional form. Books on algorithms are plenty. Many present classical algorithms as entities carved in stone, conceived decades ago, and typeset in framed pseudo-code boxes. Not so in the present book. Bird and Gibbons treat any algorithm as a subject of calculation, to be derived systemically and elegantly starting from an (almost) blank sheet that initially holds nothing but a functional specification. In fact, several of these calculations start out with incantations like solutions= filter good · candidates or algorithm= aggregate · test · generate

@article{Grust20,
  title = {Review of “Algorithm Design with Haskell” by Richard Bird and Jeremy Gibbons, Cambridge University Press, 2020.},
  author = {TORSTEN GRUST},
  journal = {Journal of Functional Programming},
  volume = {30},
  year = {2020},
  doi = {10.1017/s0956796820000258}
}