January 2012 - Annonce

TUG 2011
by Didier Verna 12 Feb '13

12 Feb '13

I'm happy to announce that my contribution to TUG 2011, the next TeX Users Group International conference, has been accepted. Please find the title and abstract below. LaTeX Coding Standards Because LaTeX (and ultimately TeX) is only a macro-expansion system, the language does not impose any kind of good software engineering practice, program structure or coding style whatsoever. As a consequence, writing beautiful code (for some definition of "beautiful") requires a lot of self-discipline from the programmer. Maybe because in the LaTeX world, collaboration is not so widespread (most packages are single-authored), the idea of some LaTeX Coding Standards is not so pressing as with other programming languages. Some people may, and probably have developed their own programming habits, but when it comes to the LaTeX world as a whole, the situation is close to anarchy. Over the years, the permanent flow of personal development experiences contributed to shape my own taste in terms of coding style. The issues involved are numerous and their spectrum is very large: they range from simple code layout (formatting, indentation, naming schemes etc.), mid-level concerns such as modularity and encapsulation, to very high-level concerns like package interaction/conflict management and even some rules for proper social behavior. In this talk, I will report on all these experiences and describe what I think are good (or at least better) programming practices. I believe that such practices do help in terms of code readability, maintainability and extensibility, all key factors in software evolution. They help me, perhaps they will help you too. -- Resistance is futile. You will be jazzimilated. Scientific site: http://www.lrde.epita.fr/~didier Music (Jazz) site: http://www.didierverna.com EPITA/LRDE, 14-16 rue Voltaire, 94276 Le Kremlin-Bicêtre, France Tel. +33 (0)1 44 08 01 85 Fax. +33 (0)1 53 14 59 22

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Séminaire Performance et Généricité du LRDE le mercredi 15 février 2012
by Daniela Becker 31 Jan '12

31 Jan '12

Chers collègues, La prochaine session du séminaire Performance et Généricité du LRDE (Laboratoire de Recherche et Développement de l'EPITA) aura lieu le Mercredi 15 février 2012 (14h-16h). Au programme: * 14h: Des performances dans les nuages avec la virtualisation des langages -- Yann Régis-Gianas http://www.pps.jussieu.fr/~yrg/ «The effective exploitation of his powers of abstraction must be regarded as one of the most vital activities of a competent programmer.» disait Dijsktra. En effet, pour aborder la complexité d'un problème, l'explicitation des concepts utiles à sa formalisation et à sa résolution est bien souvent une étape clé. Lorsque que l'on étend ce processus à une classe de problèmes qui partagent les mêmes concepts, il est naturel de se doter d'un langage le plus approprié possible pour manipuler ces abstractions spécifiques à un domaine (en anglais, «Domain Specific Language»). Comment implémenter ces DSLs? Une première approche classique reflète les constructions du DSL sous la forme d'un jeu de fonctions de bibliothèque. L'avantage de cette approche est d'utiliser directement son langage généraliste préféré, et sa chaîne de compilation optimisée, de façon à générer du code machine à moindre frais. Par contre, dans ce cadre, l'écriture de passe d'optimisations spécifiques au DSL --- à moins d'utiliser des techniques pointues de méta-programmation --- est a priori impossible. Une seconde approche, opposée, consiste à écrire un compilateur pour le DSL à partir de zéro. Toute liberté est alors donnée à l'implémenteur d'intégrer à son compilateur des passes d'optimisation spécifiques… mais au prix d'une réimplémentation de passes de compilation déjà présentes, et certainement plus abouties, dans le compilateur de son langage généraliste favori. Dans cet exposé, je présenterai les travaux de Martin Odersky et son équipe sur la virtualisation de DSLs à l'intérieur du langage de programmation Scala. La virtualisation de langage utilise intensivement le polymorphisme et la composition mixin de Scala ainsi que des techniques de génération de code à l'exécution pour embarquer des langages spécifiques dans Scala dont la compilation peut réutiliser des modules du compilateur mais aussi étendre ces derniers par des optimisations spécifiques au domaine. -- Yann Régis-Gianas est un ancien élève de l'EPITA, promo CSI 2003. À sa sortie de l'école, il a poursuivi un troisième cycle en passant un DEA à l'Université Paris Diderot et une thèse à l'INRIA Rocquencourt. Il est aujourd'hui maître de conférence à Paris Diderot et travaille sur le design des langages de programmation et de preuve. Pour plus de renseignements, consultez http://seminaire.lrde.epita.fr/. L'entrée du séminaire est libre. Merci de bien vouloir diffuser cette information le plus largement possible. -- Akim Demaille Akim.Demaille(a)lrde.epita.fr

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New technical report available for download
by Didier Verna 31 Jan '12

31 Jan '12

We are happy to announce the publication of the following new technical report, available for download and online reading: JSPP: Morphing C++ into JavaScript Christopher Chedeau, Didier Verna EPITA Research and Development Laboratory, Technical Report #201201-TR Abstract: In a time where the differences between static and dynamic languages are starting to fade away, this report brings one more element to the "convergence" picture by showing that thanks to the novelties from the recent C++0x standard, it is relatively easy to implement a JavaScript layer on top of C++. By that, we not only mean to implement the language features, but also to preserve as much of its original notation as possible. In doing so, we provide the programmer with a means to freely incorporate highly dynamic JavaScript-like code into a regular C++ program. -- Resistance is futile. You will be jazzimilated. Scientific site: http://www.lrde.epita.fr/~didier Music (Jazz) site: http://www.didierverna.com EPITA/LRDE, 14-16 rue Voltaire, 94276 Le Kremlin-Bicêtre, France Tel. +33 (0)1 44 08 01 85 Fax. +33 (0)1 53 14 59 22

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Journée "Logiciels libres et enseignement supérieur" 2 février 2012
by Daniela Becker 25 Jan '12

25 Jan '12

L'IRILL organise une journée de conférences et de discussions sur l'enseignement de technologies des logiciels libres dans l'enseignement supérieur. Le LRDE participera à cet événement qui aura lieu le jeudi 2 février 2012 dans les locaux de l'IRILL à l'antenne parisienne de l'INRIA, 23, avenue d'Italie, 75013 Paris. Pour en savoir plus : http://www.irill.org/events/lsoc-logiciels-libres-et-enseignement-superieur -- Daniela Becker Responsable administrative du LRDE

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Patcher 4.0 is released
by Didier Verna 17 Jan '12

17 Jan '12

Hello, I'm happy to announce the release of Patcher 4.0. This is a major release introducing many new changes and enhancements. Patcher is a tool designed to automate and ease the maintenance of archive-based projects. It provides assistance in building, reporting and committing patches, as well as in handling the corresponding ChangeLog entries, for example by creating skeletons. Patcher is the official tool for XEmacs development. New in this release: ** NEW FEATURES - Support floating projects and temporary relocation allowing to use the same project descriptor for various directories. - Support for automatic detection of submodules via the :submodule-detection-function project option and the patcher-detect-submodules function. Currently supported RCS submodules are Mercurial and Git via the functions 'patcher-[hg|git]-detect-submodules. - Support ephemeral ChangeLogs thanks to a new :change-logs-status project option. Ephemeral ChangeLogs are not stored in ChangeLog files, but exist only temporarily for mail or log message insertion (See ChangeLogs Status in the documentation). - ChangeLog minor mode providing easy navigation through the mail/ChangeLog buffers cycle via C-c C-p n, C-c C-p p, C-c C-p N, C-c C-p P and C-c C-p m (See ChangeLogs Navigation in the documentation). - Support for switching to mail buffer and inserting ChangeLogs at once via C-c C-p l from ChangeLog buffers. - patcher-mail-insert-change-logs gets a prefix argument allowing to temporarily change the ChangeLogs appearance. It also supports inserting ChangeLogs even when the project is set not to. - Additional binding for patcher-logmsg-commit: C-c C-p c - Commit command buffer is now editable Commit is done via C-c C-p c or C-c C-c (patcher-cmtcmd-commit). - Fontification of commit command and log message buffers with comment syntax and initial informative help. See new Patcher faces. - Support for commit or log message canceling via C-c C-z. - Support for project abortion via C-c C-p k or C-c C-k in all relevant buffers, including ChangeLogs. - Support Subject: header modification in mail adaptation routines via a new project option :subject-rewrite-format. - Support project-wide dynamic subject modification via C-c C-p S in both mail and log message buffers. - Implement :kill-source-files-after-sending project option - Support for source file saving - Support for CVS diff's broken exit code policy via a new project option: :ignore-diff-status. * FIXES AND IMPROVEMENTS - Improved support for temporary subprojects making them behave like permanent ones (with a specific subdirectory and set of files). - Much better error handling including exit code checking for external processes. - Improved support for overlapping Patcher instances through buffer and file referencing for both ChangeLog and source files. - Documentation rewrite and sections organization cleanup - More checks for project consistency including missing or spurious ChangeLog entries, source diffs, undiffable and uncommittable projects etc. - Improved project rediffing including support for partially generated ChangeLog skeletons, and interactive prompting for skeleton un/re-generation. * BACKWARD INCOMPATIBLE CHANGES - Mercurial themes renamed from 'mercurial to 'hg in order to remain consistent with the other RCS theme names. - ChangeLogs insertion in mail buffers rebound to C-c C-p l - Compressed ChangeLogs insertion in logmsg buffers rebound to C-c C-p L - Removed directory-sep-char hacks until the need for it raises again. Probably better implemented via project options anyway. - Diff commands can no longer be changed from patcher-mail-[adapt] but instead, the prefix argument allows for temporary subproject specification. - patcher-*-subproject entry points removed since they are no longer needed (see above). - Removed :kill-source-file-after-diffing option - :kill-source-files-after-sending renamed to :kill-sources-after-sending - patcher-mail-check-change-logs-insertion is now a project option named :check-change-logs-insertion. - patcher-mail-check-commit-action is now a project option named :check-commit. - :change-logs-diff-command option now understands nil instead of 'diff - The 'packed ChangeLogs appearance has been renamed to 'pack -- Resistance is futile. You will be jazzimilated. Scientific site: http://www.lrde.epita.fr/~didier Music (Jazz) site: http://www.didierverna.com EPITA/LRDE, 14-16 rue Voltaire, 94276 Le Kremlin-Bicêtre, France Tel. +33 (0)1 44 08 01 85 Fax. +33 (0)1 53 14 59 22

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ACCU 2012 session on language extensibility
by Didier Verna 03 Jan '12

03 Jan '12

Hello, and happy new year to all ! I'm pleased to announce that I will hold a 90 minutes session at the next ACCU conference in Oxford, April 2012. The session's topic is given below: Impact of Extensibility on Domain Specific Language Design and Implementation Domain-specific languages (DSLs) are usually very different from the general purpose language (GPL) in which the embedding application is written. The need for designing a DSL as a completely new language often comes from the lack of extensibility of the chosen GPL. By imposing a rigid syntax, a set of predefined operators and data structures, the traditional GPL approach leaves no choice but to implement a DSL as a different language, with its own lexical and syntactic parser, semantic analyzer and possibly its own brand new interpreter or even compiler. Some GPLs, however, are extensible or customizable enough to let one implement a DSL merely as either a subset or an extension of the original language. While the end-user does not see a difference with the traditional approach, the gain for the developer is substantial. Since the DSL is now just another entry point for the same original GPL, there is essentially only one application written in only one language to maintain. Moreover, no specific language infrastructure (parser, interpreter, compiler etc.) is required for the DSL anymore, since it is simply expressed in terms of the original GPL. The purpose of this presentation is to illustrate the most important factors that make a language truly extensible, and to show how extensibility impacts the process of DSL design and implementation. -- Resistance is futile. You will be jazzimilated. Scientific site: http://www.lrde.epita.fr/~didier Music (Jazz) site: http://www.didierverna.com EPITA/LRDE, 14-16 rue Voltaire, 94276 Le Kremlin-Bicêtre, France Tel. +33 (0)1 44 08 01 85 Fax. +33 (0)1 53 14 59 22

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