From the Book:
“Clean code that works” is Ron Jeffries’ pithy phrase. The goal is clean code that works, and for a whole bunch of reasons:
Clean code that works is a predictable way to develop. You know when you are finished, without having to worry about a long bug trail.Clean code that works gives you a chance to learn all the lessons that the code has to teach you. If you only ever slap together the first thing you think of, you never have time to think of a second, better, thing. Clean code that works improves the lives of users of our software.Clean code that works lets your teammates count on you, and you on them.Writing clean code that works feels good.But how do you get to clean code that works? Many forces drive you away from clean code, and even code that works. Without taking too much counsel of our fears, here’s what we do—drive development with automated tests, a style of development called “Test-Driven Development” (TDD for short). 
In Test-Driven Development, you:
Write new code only if you first have a failing automated test.Eliminate duplication.

Two simple rules, but they generate complex individual and group behavior. Some of the technical implications are:You must design organically, with running code providing feedback between decisionsYou must write your own tests, since you can’t wait twenty times a day for someone else to write a testYour development environment must provide rapid response to small changesYour designs must consist of many highly cohesive, loosely coupled components, just to make testing easy

The two rules imply an order to the tasks ofprogramming:
1. Red—write a little test that doesn’t work, perhaps doesn’t even compile at first
2. Green—make the test work quickly, committing whatever sins necessary in the process
3. Refactor—eliminate all the duplication created in just getting the test to work


Red/green/refactor. The TDD’s mantra.

Assuming for the moment that such a style is possible, it might be possible to dramatically reduce the defect density of code and make the subject of work crystal clear to all involved. If so, writing only code demanded by failing tests also has social implications:
If the defect density can be reduced enough, QA can shift from reactive to pro-active workIf the number of nasty surprises can be reduced enough, project managers can estimate accurately enough to involve real customers in daily developmentIf the topics of technical conversations can be made clear enough, programmers can work in minute-by-minute collaboration instead of daily or weekly collaborationAgain, if the defect density can be reduced enough, we can have shippable software with new functionality every day, leading to new business relationships with customers


So, the concept is simple, but what’s my motivation? Why would a programmer take on the additional work of writing automated tests? Why would a programmer work in tiny little steps when their mind is capable of great soaring swoops of design? Courage.
Courage
Test-driven development is a way of managing fear during programming. I don’t mean fear in a bad way, pow widdle prwogwammew needs a pacifiew, but fear in the legitimate, this-is-a-hard-problem-and-I-can’t-see-the-end-from-the-beginning sense. If pain is nature’s way of saying “Stop!”, fear is nature’s way of saying “Be careful.” Being careful is good, but fear has a host of other effects:
Makes you tentativeMakes you want to communicate lessMakes you shy from feedbackMakes you grumpy

None of these effects are helpful when programming, especially when programming something hard. So, how can you face a difficult situation and:
Instead of being tentative, begin learning concretely as quickly as possible.Instead of clamming up, communicate more clearly.Instead of avoiding feedback, search out helpful, concrete feedback.(You’ll have to work on grumpiness on your own.) 

Imagine programming as turning a crank to pull a bucket of water from a well. When the bucket is small, a free-spinning crank is fine. When the bucket is big and full of water, you’re going to get tired before the bucket is all the way up. You need a ratchet mechanism to enable you to rest between bouts of cranking. The heavier the bucket, the closer the teeth need to be on the ratchet.

The tests in test-driven development are the teeth of the ratchet. Once you get one test working, you know it is working, now and forever. You are one step closer to having everything working than you were when the test was broken. Now get the next one working, and the next, and the next. By analogy, the tougher the programming problem, the less ground should be covered by each test.

Readers of Extreme Programming Explained will notice a difference in tone between XP and TDD. TDD isn’t an absolute like Extreme Programming. XP says, “Here are things you must be able to do to be prepared to evolve further.” TDD is a little fuzzier. TDD is an awareness of the gap between decision and feedback during programming, and techniques to control that gap. “What if I do a paper design for a week, then test-drive the code? Is that TDD?” Sure, it’s TDD. You were aware of the gap between decision and feedback and you controlled the gap deliberately.

That said, most people who learn TDD find their programming practice changed for good. “Test Infected” is the phrase Erich Gamma coined to describe this shift. You might find yourself writing more tests earlier, and working in smaller steps than you ever dreamed would be sensible. On the other hand, some programmers learn TDD and go back to their earlier practices, reserving TDD for special occasions when ordinary programming isn’t making progress.

There are certainly programming tasks that can’t be driven solely by tests (or at least, not yet). Security software and concurrency, for example, are two topics where TDD is not sufficient to mechanically demonstrate that the goals of the software have been met. Security relies on essentially defect-free code, true, but also on human judgement about the methods used to secure the software. Subtle concurrency problems can’t be reliably duplicated by running the code.

Once you are finished reading this book, you should be ready to:
Start simplyWrite automated testsRefactor to add design decisions one at a time

This book is organized into three sections.
An example of writing typical model code using TDD. The example is one I got from Ward Cunningham years ago, and have used many times since, multi-currency arithmetic. In it you will learn to write tests before code and grow a design organically.An example of testing more complicated logic, including reflection and exceptions, by developing a framework for automated testing. This example also serves to introduce you to the xUnit architecture that is at the heart of many programmer-oriented testing tools. In the second example you will learn to work in even smaller steps than in the first example, including the kind of self-referential hooha beloved of computer scientists.Patterns for TDD. Included are patterns for the deciding what tests to write, how to write tests using xUnit, and a greatest hits selection of the design patterns and refactorings used in the examples.

I wrote the examples imagining a pair programming session. If you like looking at the map before wandering around, you may want to go straight to the patterns in Section 3 and use the examples as illustrations. If you prefer just wandering around and then looking at the map to see where you’ve been, try reading the examples through and refering to the patterns when you want more detail about a technique, then using the patterns as a reference.

Several reviewers have commented they got the most out of the examples when they started up a programming environment and entered the code and ran the tests as they read.

A note about the examples. Both examples, multi-currency calculation and a testing framework, appear simple. There are (and I have seen) complicated, ugly, messy ways of solving the same problems. I could have chosen one of those complicated, ugly, messy solutions to give the book an air of “reality.” However, my goal, and I hope your goal, is to write clean code that works. Before teeing off on the examples as being too simple, spend 15 seconds imagining a programming world in which all code was this clear and direct, where there were no complicated solutions, only apparently complicated problems begging for careful thought. TDD is a practice that can help you lead yourself to exactly that careful thought.

Test Driven Development: By Example

Méthodes : Sur une série de 31 femmes présentant des varices périnéales d’origine extrasaphéniennes ayant bénéficié d’une exploration radiologique veineuse pelvienne et de l’embolisation des veines incontinentes nous avons étudié les résultats et les corrélations anatomo-clinique entre les varices et les signes cliniques de l’insuffisance veineuse pelvienne. Un sous-groupe B de 23 patientes présentant une insuffisance veineuse pelvienne et des signes cliniques a été comparé à un groupe A de 4 patientes qui ne présentaient pas d’insuffisance veineuse pelvienne à l’exploration. Nous avons choisi d’étudier 3 signes cliniques : la douleur pelvienne et la douleur des membres inférieurs survenant au début ou pendant les règles ainsi que la dyspareunie. La symptomatologie a été évaluée sur une échelle analogique de 0 à 10 et un score clinique (de 0 à 30) a été établi en ajoutant ces 3 chiffres.

http://link.springer.com/content/pdf/10.1007/BF02973687.pdf

Références bibliographiques: La fibroscopie bronchique

It represents a universally applicable attitude and skill set everyone, not just computer scientists, would be eager to learn and use.

/pdf/computational-thinking-ji-suan-lun-de-si-kao-3qvv34ha3s.pdf

Computational Thinking 計算論的思考

/pdf/comparing-children-s-online-opportunities-and-risks-across-1i677vk2z4.pdf

Comparing children’s online opportunities and risks across Europe: cross-national comparisons for EU Kids Online

To understand information processing on blogs, this study investigates how perceived blogger trustworthiness affects blog readers’ elaboration of brand-related messages and its interaction effects with argument quality. The results reveal that the degree of perceived blogger trustworthiness affects the extent of message elaboration, and findings from a 2 × 2 (perceived blogger trustworthiness × argument quality) factorial experiment suggest a significant interaction effect on brand attitudes. This interaction reveals that when perceived blogger trustworthiness is high, argument quality has a greater impact on brand attitudes than when perceived blogger trustworthiness is low. The authors discuss some implications and suggestions for further research.

The Effect of Perceived Blogger Credibility and Argument Quality on Message Elaboration and Brand Attitudes

Les rapports entre l’institution scolaire et la culture numerique des eleves sont ici examines a la lumiere d’une recherche qualitative centree sur les collegiens d’un etablissement scolaire. L’institution scolaire est confrontee aux pratiques personnelles des eleves, qui inscrivent l’usage des TIC dans le processus de construction de soi et d’autonomisation de leurs pratiques culturelles et de communication. Certaines difficultes de l’integration scolaire des TIC sont dues au caractere limite et local des competences techniques developpees par les eleves, associe a une faible conceptualisation et verbalisation des pratiques ordinaires. Meme dans l’utilisation d’outils logiciels communs aux deux univers, on peut reperer une structuration differente de l’activite qui fait obstacle au reinvestissement scolaire des competences techniques.

/pdf/l-ecole-a-l-epreuve-de-la-culture-numerique-des-eleves-b9vxvpsqo4.pdf

L’école à l’épreuve de la culture numérique des élèves

Dans leurs pratiques personnelles avec les technologies de l'information et de la communication, les eleves developpent certaines competences, notamment techniques, dont on pourrait penser qu'elles sont directement disponibles en contexte scolaire. Ce n'est pas vraiment le cas et cette communication analyse quelques obstacles a la mobilisation scolaire de ces competences techniques. Apres avoir rappele que la similarite, voire l'identite, des outils utilises peut recouvrir des finalites tres differentes, plusieurs elements sont mis en avant. D'une part, est souligne le caractere limite des connaissances techniques, rendant delicate une decontextualisation qui permettrait un transfert entre les univers personnels et scolaires. D'autre part, le fait que les gestes mis en œuvre peuvent eux-memes fortement differer suivant le contexte d'usage. Ce dernier point est illustre par l'exemple des schemes de navigation en et hors contexte scolaire.

https://archivesic.ccsd.cnrs.fr/sic_00343128/document

TIC : analyse de certains obstacles à la mobilisation des compétences issues des pratiques personnelles dans les activités scolaires

Les jeunes adolescents sont couramment depeints comme familiers des TIC, accultures depuis l'enfance a leur usage et particulierement experts dans leur manipulation. Cette these vise a saisir, au-dela de l'hypothese de sens commun d'un « bain » dans lequel baigneraient les jeunes actuels, le processus d'appropriation des ordinateurs par les jeunes adolescents. Le cadre conceptuel propose articule les apports de la sociologie dispositionnaliste de Bernard Lahire, qui permet de rendre compte de la pluralite des univers d'appropriation, et les concepts de scheme d'utilisation et d'instrument, developpes par l'approche instrumentale de Pierre Rabardel, qui permet de caracteriser ce qui s'incorpore dans l'usage des outils informatiques et de rendre compte de la nature instrumentale des logiques d'action mises en oeuvre. La these montre que le developpement des usages et du jeu des competences techniques est etroitement articule a la construction de soi et aux formes de sociabilite adolescentes, mais que la pluralite des univers d'usage des outils informatiques conduit a une pluralite des formes d'appropriation, source d'une differenciation interpersonnelle et d'une heterogeneite interne des dispositions et schemes d'utilisation incorpores. L'appropriation generationnelle, ludique et pragmatique, conduit a une familiarisation pratique permettant l'incorporation de savoir-faire locaux ; l'appropriation familiale passant par la transmission de ce que nous analysons comme un capital informatique conduit a une variabilite inter-individuelle des dispositions a l'usage ; tandis que l'appropriation scolaire, en rupture avec les usages familiers aux eleves, conduit a une manipulation consciente et structuree produisant une variabilite intra-individuelle des schemes d'utilisation.

https://tel.archives-ouvertes.fr/tel-00422204/document

L'appropriation des TIC par les collégiens dans les sphères familières et scolaires

Dans le contexte d’une diffusion massive des blogs parmi les adolescents, 
cet article etudie l’appropriation des Skyblogs dans un groupe de collegiens. 
Nous appuyant sur une enquete ethnographique dans un college populaire, 
nous etudions le processus d’appropriation des blogs, envisages comme des 
instruments dans des activites finalisees et comme le fruit d’une activite 
constructive de la part des utilisateurs. Nous montrons que pour les 
collegiens la signification que prennent les blogs evolue, suivant le 
developpement des formes de leur sociabilite et leur construction identitaire. 
Pour les plus jeunes des collegiens les blogs sont avant tout utilises comme 
instrument d’incorporation des normes et valeurs de la culture juvenile, les 
plus âges creant des blogs envisages comme des outils au service de 
l’expressivite au sein du groupe.

/pdf/la-sociabilite-juvenile-instrumentee-4utfsyunwe.pdf

La sociabilité juvénile instrumentée

Les etudiants disposent d’une large palette d’instruments de communicationinterpersonnelle et d’acces a l’information. Cet article vise a explorer les relations entre lespratiques de communication ordinaires des etudiants et les pratiques educatives en contexteuniversitaire, en considerant que les pratiques ordinaires constituent de fait une forme dedistance presente dans le superieur. Est ainsi mise en evidence l’existence de plusieursformes de distances dans les formations, dont les caracteristiques sont analysees dans uneperspective instrumentale au regard de resultats en sociologie des usages.

https://hal.univ-lille.fr/hal-01613661/document

Cédric Fluckiger

Papers

L’école à l’épreuve de la culture numérique des élèves

TIC : analyse de certains obstacles à la mobilisation des compétences issues des pratiques personnelles dans les activités scolaires

L'appropriation des TIC par les collégiens dans les sphères familières et scolaires

La sociabilité juvénile instrumentée

De l'émergence de nouvelles formes de distance: Les conséquences des nouvelles pratiques de communication ordinaires sur la FAD dans le supérieur