The Coq mailing list

[Matthieu Sozeau <matthieu.sozeau AT inria.fr>]

Dear Coq-Club members,

The Coq development team is pleased to announce the release of the first beta
version of Coq 8.5 at http://coq.inria.fr/. The new available features 
include:

- asynchronous edition of documents under CoqIDE to keep working on a
  proof while Coq checks the other proofs in the background (by Enrico
  Tassi);
- universe polymorphism making it possible to reuse the same
  definitions at various universe levels (by Matthieu Sozeau);
- primitive projections improving space and time efficiency of
  records, and adding eta-conversion for records (by Matthieu Sozeau);
- extensions of the new proof engine featuring dependent subgoals
  management, fully backtracking tactics, as well as tactics which can
  consider multiple goals together (by Arnaud Spiwack);
- a new reduction procedure called native_compute to evaluate terms
  using the OCaml native compiler, for proofs with large computational
  steps (by Maxime Dénès).

The main other changes are:

- a new fast compilation chain that skips checking of proofs (producing
  .vio files);
- a new construct $(..)$ to call tactics from term definitions;
- a more restrictive guard condition to recover compatibility with axioms
  like propositional extensionality and (some consequences of) univalence;
- a new option -type-in-type to collapse the universe hierarchy (makes
  the logic inconsistent but useful for exploration);
- a better-behaved alternative to simpl, called cbn;
- various improvements to the tactic language, like a new introduction
  pattern [= x1 ... xn] which applies injection on the fly (inspired
  by SSReflect); new constructs uconstr:c and type_term c to build
  untyped terms in Ltac;
- significant improvements of general efficiency.

See http://coq.inria.fr/ for more details, and the CHANGES file in the
distribution for a comprehensive list.

The Coq development team whishes to acknowledge the many
people which made Coq 8.5 possible: Pierre Boutillier,
Pierre Courtieu, Maxime Dénès, Hugo Herbelin, Pierre Letouzey,
Pierre-Marie Pédrot, Yann Régis-Gianas, Matthieu Sozeau, Arnaud
Spiwack, Enrico Tassi with contributions also from Bruno Barras, Yves
Bertot, Frédéric Besson, Xavier Clerc, Pierre Corbineau,
Jean-Christophe Filliâtre, Julien Forest, Sébastien Hinderer, Assia
Mahboubi, Guillaume Melquiond, Jean-Marc Notin, François Ripault,
Carst Tankink as well as many external contributors.

The Coq Development Team