[ANN] Dezyne 2.15.0 released as Free Software

[Jan Nieuwenhuizen]

We are thrilled to announce Dezyne 2.15: Dezyne is now being released as
Free Software (FLOSS).

* About

Dezyne[0] is a programming language and a set of tools to specify,
validate, verify, simulate, document, and implement concurrent control
software.

The Dezyne language has formal semantics expressed in mCRL2[1] developed at
the department of Mathematics and Computer Science of the Eindhoven
University of Technology (TUE[2]).  Dezyne requires that every model is
finite, deterministic and free of deadlocks, livelocks, and contract
violations.  This achieved by means of the language itself as well as
by builtin verification through model checking.  This allows the
construction of complex systems by assembling independently verified
components.

* Summary

This release completes full support for blocking: This finally marks
the Grand Unification into single threaded execution semantics.

The documentation has seen a major rewrite and is available here:
<https://dezyne.org/documentation.html>.

We will evaluate your reports and track them via the
Gitlab dezyne-issues project[3], see our guide to writing
helpful bug reports[4].

* What's next?

Verification with system scope and automatically exploring possible
traces in a system.  Introducing a new keyword `defer' for asynchronous
behavior and deprecation of `async'.

* Future

Looking beyond the next releases we will introduce implicit interface
constraints.  Hierarchical behaviors, module-specifications and
data-interfaces.  Support for Model Based Testing.

Please do not hesitate to forward this announcement to other fora
interested in formal methods and verification!

Enjoy!
The Dezyne developers.

* Download

  git clone git://git.savannah.nongnu.org/dezyne.git

  Here are the compressed sources and a GPG detached signature[*]:
    https://dezyne.org/download/dezyne/dezyne-2.15.0.tar.gz
    https://dezyne.org/download/dezyne/dezyne-2.15.0.tar.gz.sig

  Here are the SHA1 and SHA256 checksums:

    395ff05e4f2c17bcee895fd9436d696fb0aab93d  dezyne-2.15.0.tar.gz
    982d8f7cca9de23225e2f06b4c8524c0b57acfba81beaaff1a0c045c1e6409ea  
dezyne-2.15.0.tar.gz

  [*] Use a .sig file to verify that the corresponding file (without the
  .sig suffix) is intact.  First, be sure to download both the .sig file
  and the corresponding tarball.  Then, run a command like this:

    gpg --verify dezyne-2.15.0.tar.gz.sig

  If that command fails because you don't have the required public key,
  then run this command to import it:

    gpg --keyserver keys.gnupg.net --recv-keys 
1A858392E331EAFDB8C27FFBF3C1A0D9C1D65273

  and rerun the 'gpg --verify' command.

  Alternatively, Dezyne can be installed using GNU Guix[5]:
    guix pull
    guix install dezyne

* NEWS

* Changes in 2.15.0 since 2.14.0
** Language
  - Blocking is now fully supported, it may be used:
    + In non-toplevel components,
    + In a component with multiple provides ports, but see the
      `Blocking' section in the manual for caveats.
    + A new `blocking' qualifier for ports must be used if a port can
      block, or block collateraly.
  - Using unobservable non-determinism in interfaces is no longer
    supported.
  - An action or function call can now also be used in a return
    expression (#67[5]).  Note that recursive functions still cannot be
    valued.
** Commands
  - The `dzn explore' command has been removed.
** Verification
  - The verifier now supports blocking for components with multiple
    provides ports.
  - The verifier now detects possible deadlock errors due to a requires
    action blocking collaterally, which could happen when a component
    deeper in the system hierarchy uses blocking.
  - The option `--no-interface-determinism' has been removed for `dzn
    verify'.
** Simulation
  - The simulator now supports collateral blocking.
  - In interactive mode:
    + The new `,state' command shows the state (#66[6]),
    + The new `,quit' command exits the session,
    + The simulator does not exit when supplying empty input.
  - The simulator now detects possible deadlock errors due to a requires
    action blocking collaterally, which could happen when a component
    deeper in the system hierarchy uses blocking.
  - The simulator now detects livelocks in interfaces at end of trail.
  - The simulator now detects queue-full errors caused by external at
    end of trail.
  - The `dzn simulate' command now supports the `-C,--no-compliance',
    `--no-interface-livelock' and `-Q,--no-queue-full' options,
** Code
  - The C++ and C# code generators and runtime now fully support
    collaterally blocking components.
** Views
  - Returns are no longer removed from the state-diagram.  Using the new
    `--hide=returns' (or `--hide=actions') now removes void action
    returns.
** Documentation
  - Blocking has been updated and extended.
  - A new section on foreign components was added.
** Noteworthy bug fixes
  - Using the construct `provides external' (which has no semantics) no
    longer confuses the simulator.
  - A bug has been fixed that would cause the well-welformness check for
    system bindings to ignore certain missing bindings.
  - A bug has been fixed when assigning a value to a formal parameter of
    a function.
  - A bug has been fixed in the vm that would cause graph or simulate to
    hang when using a foreign component that has both provides and
    requires ports (note: don't do that!).
  - The test framework can be built using gcc-11.
  - A bug has been fixed in the code generator when assiging to a local
    variable that shadows a formal parameter or member variable.
  - A bug has been fixed in the verifier when creating a new local
    variable or assigning a variable that remains otherwise unused.
  - The simulation function now supports injection of foreign
    components.
  - The trace produced by running dezyne code is now correct when using
    injected foreign components.
  - A bug has been fixed that would cause the verifier to overlook
    non-determinism in a component.
  - Using external data in binary expressions is now reported as an
    error (#64[7]).
  - The parser no longer reports "<unknown-type>" expected when an
    external type definition is missing.
  - The well-formedness check of the parser no longer hangs when a
    component has the same name as one of its interfaces.
  - An interface can now have the same name as its namespace.

* Links

[0] https://dezyne.org
[1] https://mcrl2.org
[2] https://tue.nl
[3] https://gitlab.com/groups/dezyne/-/issues
[4] https://dezyne.org/bugreport
[5] https://gitlab.com/dezyne/dezyne-issues/-/issues/67
[6] https://gitlab.com/dezyne/dezyne-issues/-/issues/66
[7] https://gitlab.com/dezyne/dezyne-issues/-/issues/61

-- 
Jan Nieuwenhuizen <janneke@gnu.org>  | GNU LilyPond https://lilypond.org
Freelance IT https://JoyOfSource.com | Avatar® https://AvatarAcademy.com