Record of Overture NM16, 4 March 2007, 1200 CET

Participants: John Fitzgerald, Peter Gorm Larsen, Hugo Macedo, Shin Sahara, Marcel Verhoef

Review of Action List

The actions are all at Overture on SourceForge.

13/2 is ongoing and is an expected outcome of the Mondex work.

14/2 remains open. Discussed further when considering the research agenda.

15/2 open. Thomas is still not finished with his SS work and the talked completion date is end of April.

15/3 open.

15/4 open.

15/5 closed. Done.

VDMTools

Status of VDMTools development

The proof obligation generator spec to take the new VICE extensions into account was updated by Peter. Shin will make bug reports of it at the end of March.

Bug reporting for VDMTools bugs

A URL is being set up for bug reports and Shin will report on how to access and use it.

Action 16/1 Shin to report on VDMTools bug reporting usage.

Overture

Status of Thomas' work on the Overture type checker

Thomas is almost finished with his work but he needs to concentrate on his thesis writing at the moment. He has not dealt with operations, inheritance and instance variables and probably he will not get time to do that. His focus has been on investigation whether it is possible to do type derivation in the same way as for ML for polymorphic functions and typeless functions. This is not a problem for the other work on the tools.

Status of Hugo's work on the Overture interpreter

Hugo sent a short report on the actual achievements on the Overture Interpreter which are the confirmation of the feasibility of the ideas that precede his project. One idea is to translate the OML classes to byte code and use JVM to debug; the alternative is to specify our own Virtual Machine refactoring and reusing some actual specifications. The second approach is being studied. Further feedback on the vital decision between JVM or the internal approach will be given off line by Marcel.

Status of Sander's work on the Overture proof support

Sander was travelling, so John reported. We can generate and prove a PO from the simplest case study and are making progress at generating theories and tactics sufficient to deal with more complex ones. The hardest are those with an existential quantifier because of the need to generate a witness value. The various improvements that have taken place between HOL98 and HOL4 are making some aspects of the project simpler than we expected.

Sander's visit to Ncl took place last week and was well timed. Cliff and John are investigating characterizations of LPF and they had a visit from Jim Woodcock on the same subject. So there was a chance for Sander to see something of the longer-term research issues as well as working on the shorter-term goals of updating Prosper.

Mondex and Pacemaker case studies

Jeremy Bryans reported that several people have expressed interest in tackling Mondex in VDM, and that he is leading this work from Newcastle. A workshop is scheduled for 2-3 April at Newcastle for the interested people to make concrete progress. Prior to that, a reading group at Newcastle will review the monograph that describes the Mondex study in Z.

John reported that the Newcastle team is using this as an opportunity to learn VDM++ as they go, and this is doing a great deal widen the skills base for Overture.

There was some discussion of real time and stochastic extensions. Marcel reported very good results introducing an element of stochastic modeling into the RT extensions that he has been working on for the final chapter of his PhD.

Publication plans

In preparation:

• Traces Paper (John, Peter, Simon, Marcel), due early April.
• The Goldsmith Conjecture and LPF (John, Cliff) due early April for Information Processing Letters.
• Paper path case study (Marcel) for SCSC ( aleading simulation conference).
• Encyclopedia of Computer Science & Engineering entry on "VDM" (John, Peter, Marcel) due 25 May
• Wikipedia entry on VDM (John) aiming for 25 May as well.
• Marcel's thesis.

In review:

• Water Tank case study (IFM)

In press:

• Isola keynote (John, Peter) in Isola proceedings (John checking publication date with editors).
• Dynamic Coalitions (Jeremy, John) in Isola proceedings (John checking publication date with editors).
• The LPF and VDM (John) in Dines and Martin Henson's new book (with publisher).

Any Other Business

Nothing to report.

Next Meeting

8 Apr 2007 1200 CET

-- HugoMacedo - 02 Mar 2007 -- JohnFitzgerald - 04 Mar 2007