anchor.diff:  Project Maturity
   ~~~~~~~~~~~~~~~~
   
  -Since _cats_ is a young project there can be some link:codox/index.html#id[API]
  -breakage.
  +Since _cats_ is a young project there can be some link:codox/index.html#id[API] breakage.
   
   
   Install
  
positive.code: State
  +++++
  
  TODO
  
  Reader
  ++++++
  
negative.code: ;; => #<Either [:bar :right]>
  ----
  
  If you not understand the purpose of **pure** function, it is possible that the next section
  can clarify the real purpose of it.
  
  
  Monad
  ~~~~~
  