Current Developments

This page sum up the known developments that are being done around or for the Rodin Platform. Please contributes informations about your own development to keep the community informed

Deploy Tasks

The following tasks were planned at some stage of the Deploy project.

Core Platform

Rodin Index Manager

Systerel is in charge of this task.

For more details on Rodin index design, see Rodin Index Design.

The purpose of the Rodin index manager is to store in a uniform way the entities that are declared in the database together with their occurrences. This central repository of declarations and occurrences will allow for fast implementations of various refactoring mechanisms (such as renaming) and support for searching models or browsing them.

Text Editor

The efforts in Düsseldorf (Fabian) and Newcastle (Alexei) have been joined to create a single text editor which will be part of the EMF framework for Rodin (see that section for details).

EMF framework for Rodin

Newcastle, Southampton and Düsseldorf have begun to develop an EMF framework to support Rodin modelling tools based on EMF. The framework includes an EMF representation of Event-B, a synchronising persistence interface for loading and saving models via the Rodin API and facilities to support text editing and parsing. Examples of tools that will be based on the EMF framework for Rodin are, a Text editor, a compare/merge editor (which can be used for team based development), pattern/composition tools, Diagram Editors.

More details can be found here: EMF framework for Rodin

Plug-ins

Requirement Management Plug-in

Michael at Düsseldorf is in charge of the Requirements Management Plug-in.

See also: Requirements Management Plug-in and Requirements Tutorial

This plug-in allows:

• Requirements to be edited in a set of documents (independently from Rodin)
• Requirements to be viewed within Rodin
• Individual Requirements to be linked to individual Event-B-Entities
• A basic completion test to be performed

UML-B Plug-in

Southampton is in charge of UML-B plug-in.

• Support for synchronisation of transitions from different statemachines. This feature will allow two or more transitions in different statemachines to contribute to a single event. This feature is needed because a single event can alter several variables (in this case statemachines) simultaneously.

• Allow user to allocate the name of the 'implicit contextual instance' used in a class. Events and Transitions owned by a class are implicitly acting upon an instance of the class which has formerly been denoted by the reserved word 'self'. This modification allows the modeller to override 'self' (which is now the default name) with any other identifier. This feature is needed to avoid name clashes when synchronising transitions into a single event. It also allows events to be moved between different classes (or outside of all classes) during refinement without creating name clashes.

• Better support for state machine refinement in UML-B. This revision to UML-B allows a statemachine to be recognised as a refinement of another one and to be treated in an appropriate way during translation to Event-B. The states and transitions of a refined statemachine can be elaborated by adding more detailed hierarchical statemachines.

ProB Plug-in

Düsseldorf is in charge of ProB.

Work already performed

We have now ported ProB to work directly on the Rodin AST. Animation is working and the user can now set a limited number of preferences. The model checking feature is now also accessible. It is also possible to create CSP and classical B specification files. These files can be edited with BE4 and animated/model checked with ProB. On the classical B side we have moved to a new, more robust parser (which is now capable of parsing some of the more complicated AtelierB specifications from Siemens).

On the developer side, we have moved to a continuous integration infrastructure using CruiseControl. Rodin is also building from CVS in that infrastructure.

Ongoing and future developments

We are currently developing a new, better user interface. We also plan to support multi-level animation with checking of the gluing invariant.

We have prototypes for several extensions working, but they need to be fully tested and integrated into the plugin:

• an inspector that allows the user to inspect complex predicates (such as invariants or guards) as well as expressions in a tree-like manner
• a graphical animator based on SWT that allows the user to design his/her own animations easily within the tool
• a 2D viewer to inspect the state space of the specification

B2Latex Plug-in

Southampton is in charge of B2Latex.

Kriangsak Damchoom will update the plug-in to add extensions of events.

Parallel Composition Plug-in

Southampton is in charge of the Parallel Composition using Event-B .

The intention of the plug-in is to allow the parallel composition of events using Event-B syntax. The composition uses a value-passing style (shared event composition), where parameters can be shared/merged.

This plug-in allows:

• Selection of machines that will be part of the composition (Includes Section)
• Possible selection of an abstract machine (Refines Section)
• Possible inclusion of invariants that relate the included machines (Invariant Section and use of the monotonicity )
• Invariants of included machines are conjoined.
• Selection of events that will be merged. The event(s) must come from different machines. At the moment, events with parameters with same name are merged. If it is a refinement composition, it is possible to choose the abstract event that is being refined.
• Initialisation event is the parallel composition of all the included machines' initialisations.
• For a composed event, the guards are conjoined and the all the actions are composed in parallel.

Currently, after the conclusion of the composition machine, a new machine can be generated, resulting from the properties defined on the composition file. This allows proofs to be generated as well as a visualisation of the composition machine file. In the future, the intention is to make the validation directly on the composition machine file directly where proofs would be generated ( and discharged) - the new machine generation would be optional. An event-b model for the validation/generation of proofs in currently being developed. Another functionality which should be quite useful for the composition (but not restricted to that) is renaming:

• while composing, two machines may have variables with the same name for instance (which is not allowed for this type of composition). In order to solve this problem, one would have to rename one of the variables in order to avoid the clash, which would mean change the original machine. A possible solution for that would be to rename the variable but just on composition machine file, keeping the original machine intact. A renaming framework designed and developed by Stefan Hallerstede and Sonja Holl exists currently although still on a testing phase. The framework was developed to be used in a general fashion (not constrained to event-b syntax). The idea is to extend the development of this framework and apply to Event-B syntax (current development).

There is a prototype for the composition plug-in available that works for Rodin 0.8.2. A release for the Rodin 0.9 is concluded and will be available from the Rodin Main Update Site soon, under 'Shared Event Composition' update.

Measurement Plug-In

The Measurement Plug-In to the RODIN platform will provide information both about the model itself and about the process of building the model. It has a double purpose:

• provide feedback to the user about the quality of the Event-B model he is building and about potential problems in it or in the way he is building it.
• automate the data collection process for the measurement and assessment WP. This data collected will be analyzed to identify global transfer (increase in model quality, size, complexity,...), tool shortcomings (usability, prover), modelling issues (to be addressed by training, language, tool evolution,...), etc.

Exploratory Tasks

One Single View

Maria is in charge of this exploratory work during is internship.

For more details on Single View Design, see Single View Design.

The goal of this project is to present everything in a single view in Rodin. So the user won't have to switch perspectives.

Others

AnimB

Christophe devotes some of its spare time for this plug-in.

For more details on AnimB Current Developments, see AnimB Current Developments.

The current developments around the AnimB plug-in encompass the following topics:

Live animation update

where the modification of the animated event-B model is instantaneously taken into account by the animator, without the need to restart the animation.

Collecting history

The history of the animation will be collected.

Team-Based Development

Usage Scenarios

In order to understand the problem properly, Düsseldorf created a number of usage Scenarios for Team-based Development.

A page as also been opened for merging proofs scenarios.

B2C

This plug-in translates Event-B models to C source code, which may then be compiled using external C development tools. Steve wrote B2C with the specific purpose of translating the MIDAS model, an Event-B implementation of a Virtual Machine instruction set.

B2C supports a sub-set of Event-B that can be easily translated to C form. The user provides a final refinement step that does nothing except restate the model in this translatable form: symbolic constants must be replaced by their literal values, range membership guards are replaced by greater-than and less-than guards, and actions are restated not to use global statments on their left-sides (this because the variable may have been modified by an earlier action, and may not be valid). The manipulations are done within EventB where they can be checked by the Proof Obligation system, and B2C made as simple as possible to maximise reliability. This re-write process is currently a manual step, but could in principle be done by another plug-in

B2C source code is not currently available for download: contact Steve directly if it is required.

New Proof Rules

This document describes the set of newly added reasoners for improving the usability of the prover within Rodin Platform.