Difference between pages "D32 Mathematical Extensions" and "D32 Teamwork"

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imported>Nicolas
 
imported>Renato
 
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=== Overview ===
 
=== Overview ===
 +
Teamwork consists of
 +
* SVN enabling teamwork plug-in
 +
* Decomposition methods
  
Mathematical extensions have been co-developed by Systerel (for the Core Rodin Platform) and Southampton (for the Theory plug-in). The main purpose of this new feature was to provide the Rodin user with a way to extend the standard Event-B mathematical language, by defining his own mathematical operators, basic predicates and algebraic types. Along with these additional notations, the user can also define new proof rules (prover extensions).
 
  
A theory is a file that gathers of new algebraic types, new operators/predicates and new proof rules. It is developed in the Rodin workspace. When it is complete, the user makes it available to his models (this action is called the deployment of a theory). He can then start using his own operators, datatypes and proof rules for the development of his models.
+
* Team-working Plug-in is a new feature developed by University of Southampton in request to industrial partners who required support of Rodin project management and team development using Subversion system. Having this support would bring the benefit of centralised model storage and versioning, as well as parallel development. Despite a few functional limitations, derived by specific nature of the Rodin projects, the implemented plug-in gives support for Subversion-based project sharing and collaborative development.
 +
 
 +
* Decomposition plug-in was developed by Renato Silva (University of Southampton), Carine Pascal (Systerel) based on the initial prototype developed by T.S. Hoang (ETH Zurich). This plug-in was developed as an answer to models that became to big to be handled with a large number of events, a large number of variables and consequently a large number of proof obligations over several levels of refinements. There are two kinds of decomposition available: ''shared event'' (studied initially by Michael Butler) and ''shared variable'' (studied initially by Jean-Raymond Abrial). Both decomposition styles allow the partition of the original model into (smaller) sub-models. The sub-models are expected to be easier to handle, with less variables and less events and less proof obligations. This partition is done in a way that the sub-models (also referred as sub-components) are independent of each other and therefore can be refined individually. As a consequence, each sub-model can be further developed by different people allowing teamwork development.
  
 
=== Motivations ===
 
=== Motivations ===
 +
Main reasons for implementing teamwork are:
 +
* SVN Teamwork
 +
: The reason to support compatibility of Rodin projects with Subversion was to allow Rodin users to share their projects and work on them together, as well as have the benefits of versioning and revision control, provided by the SVN system. It was difficult to work on models in parallel and manage changes made by different parties, especially for big and complex models. Other users expressed a concern on safety aspect of collaborative development, thus pointing out the benefits of centralised repository storage of the models under development on SVN.
  
Main reasons for implementing mathematical extensions are:
+
* Decomposition
* increased readability (<math>a \; \operatorname{OR} \; b</math> rather than <math>\operatorname{bool}(a=TRUE \or b=TRUE)</math>)
+
: Difficulties in managing complex models (in particular for a large number of proof obligations) fed the idea of decomposing a model in a way that the resulting sub-models could be developed by different individuals. The decomposition process should be seen as a refinement step where the original properties and respective proof obligations should remain valid. With shared event and shared variable decomposition, these requirements are preserved, with the advantage of simplifying the overall development by dealing with sub-parts of the model at once in each sub-model.
* polymorphism (<math>l \in List(S \cprod T)</math>)
 
* decreased proving effort, thanks to extension specific proof rules instead of general purpose ones
 
  
 
=== Choices / Decisions ===
 
=== Choices / Decisions ===
 
+
* SVN Teamwork
On the Core Rodin Platform side, implementing mathematical extensions required to make some parts of the code extensible, that were not designed to be so, namely the lexer and the parser. We were using tools that automatically generated them from a fixed grammar description, so we had to change to other technologies. A [http://wiki.event-b.org/index.php/Constrained_Dynamic_Parser study] has been made on available technologies. The Pratt algorithm was selected for its adequation with the purpose and it did not have the drawbacks of other technologies:
+
: The desired objective of a plug-in that would bring support for Subversion in Rodin was to make a Rodin project compatible with standard SVN interface. Due to nature of the Rodin resource management, in particular the use of Rodin database and non-XMI serialisation, it turned out a hard task. A solution to this difficulty was to provide an alternative serialisation method, that would be compatible with Subversion interface. XMI serialisation has been chosen in the final plug-in, which together with Event-B EMF framework provides a shareable copy of the resources of a Rodin project and takes care of synchronisation between two.
* foreign language integration
 
* overhead due to over generality
 
 
 
After a mocking up phase to verify feasibility, the Pratt algorithm has been confirmed as the chosen option and implemented in the Rodin Platform.
 
 
 
Besides, we wanted to set up a way to publish and share theories for Rodin users, in order to constitute a database of pre-built theories for everyone to use and contribute. This has been realised by adding a new tracker on SourceForge site ([http://sourceforge.net/tracker/?group_id=108850&atid=1558661]).
 
  
 
=== Available Documentation ===
 
=== Available Documentation ===
 
+
* SVN Team-based development documentation<ref>http://wiki.event-b.org/index.php/Team-based_development</ref>
{{TODO|add pdf mathextn from BSCW}}
 
 
 
* Requirements.
 
* Pre-studies (states of the art, proposals, discussions).
 
** [http://wiki.event-b.org/index.php/Constrained_Dynamic_Parser#Design_Alternatives]
 
* Technical details (specifications).
 
** [http://wiki.event-b.org/index.php/Mathematical_Extensions]
 
** [http://wiki.event-b.org/index.php/Constrained_Dynamic_Lexer]
 
** [http://wiki.event-b.org/index.php/Constrained_Dynamic_Parser]
 
** [http://wiki.event-b.org/index.php/Theory_Plug-in]
 
* Teaching materials (tutorials).
 
* User's guides.
 
** [http://wiki.event-b.org/images/Theory_UM.pdf]
 
  
 
=== Planning ===
 
=== Planning ===
 
This paragraph shall give a timeline and current status (as of 28 Jan 2011).
 
This paragraph shall give a timeline and current status (as of 28 Jan 2011).
 +
 +
=References=
 +
<references/>
  
 
[[Category:D32 Deliverable]]
 
[[Category:D32 Deliverable]]

Revision as of 11:11, 26 November 2010

Overview

Teamwork consists of

  • SVN enabling teamwork plug-in
  • Decomposition methods


  • Team-working Plug-in is a new feature developed by University of Southampton in request to industrial partners who required support of Rodin project management and team development using Subversion system. Having this support would bring the benefit of centralised model storage and versioning, as well as parallel development. Despite a few functional limitations, derived by specific nature of the Rodin projects, the implemented plug-in gives support for Subversion-based project sharing and collaborative development.
  • Decomposition plug-in was developed by Renato Silva (University of Southampton), Carine Pascal (Systerel) based on the initial prototype developed by T.S. Hoang (ETH Zurich). This plug-in was developed as an answer to models that became to big to be handled with a large number of events, a large number of variables and consequently a large number of proof obligations over several levels of refinements. There are two kinds of decomposition available: shared event (studied initially by Michael Butler) and shared variable (studied initially by Jean-Raymond Abrial). Both decomposition styles allow the partition of the original model into (smaller) sub-models. The sub-models are expected to be easier to handle, with less variables and less events and less proof obligations. This partition is done in a way that the sub-models (also referred as sub-components) are independent of each other and therefore can be refined individually. As a consequence, each sub-model can be further developed by different people allowing teamwork development.

Motivations

Main reasons for implementing teamwork are:

  • SVN Teamwork
The reason to support compatibility of Rodin projects with Subversion was to allow Rodin users to share their projects and work on them together, as well as have the benefits of versioning and revision control, provided by the SVN system. It was difficult to work on models in parallel and manage changes made by different parties, especially for big and complex models. Other users expressed a concern on safety aspect of collaborative development, thus pointing out the benefits of centralised repository storage of the models under development on SVN.
  • Decomposition
Difficulties in managing complex models (in particular for a large number of proof obligations) fed the idea of decomposing a model in a way that the resulting sub-models could be developed by different individuals. The decomposition process should be seen as a refinement step where the original properties and respective proof obligations should remain valid. With shared event and shared variable decomposition, these requirements are preserved, with the advantage of simplifying the overall development by dealing with sub-parts of the model at once in each sub-model.

Choices / Decisions

  • SVN Teamwork
The desired objective of a plug-in that would bring support for Subversion in Rodin was to make a Rodin project compatible with standard SVN interface. Due to nature of the Rodin resource management, in particular the use of Rodin database and non-XMI serialisation, it turned out a hard task. A solution to this difficulty was to provide an alternative serialisation method, that would be compatible with Subversion interface. XMI serialisation has been chosen in the final plug-in, which together with Event-B EMF framework provides a shareable copy of the resources of a Rodin project and takes care of synchronisation between two.

Available Documentation

  • SVN Team-based development documentation[1]

Planning

This paragraph shall give a timeline and current status (as of 28 Jan 2011).

References