[Caml-list] [ANN] New release of visitors

["François Pottier" <francois.pottier@inria.fr>]

Dear OCaml users,

It is my pleasure to announce release 20170308 of the "visitors" package,
a syntax extension that makes it easy to generate visitor classes for
algebraic data structures.

The major additions since the previous release are as follows:

- A new option [polymorphic = true] allows generating visitor methods with
   polymorphic types. With [polymorphic = true], a type variable ['a] is
   handled by a visitor *function* [visit_'a], which is passed as an 
argument
   to every visitor method; whereas, with [polymorphic = false], a type
   variable ['a] is handled by a virtual visitor *method* [visit_'a].
   With [polymorphic = true], visitor classes compose better,
   and irregular algebraic data types are supported.

- A new variety of visitor, "mapreduce", computes a pair of a data structure
   (like a "map" visitor) and a summary (like a "reduce" visitor). This 
can be
   used to annotate every tree node with information about the subtree that
   lies below it.

There are also several minor new features and documentation additions.

To install the package via opam, use the following commands:

   opam update
   opam install visitors

The documentation is here:

   http://gallium.inria.fr/~fpottier/visitors/manual.pdf

Have fun,

--
François Pottier
francois.pottier@inria.fr
http://gallium.inria.fr/~fpottier/