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CppCon 2014: John Lakos "Defensive Programming Done Right, Part I"

http://www.cppcon.org — Presentation Slides, PDFs, Source Code and other presenter materials are available at: https://github.com/CppCon/CppCon2014 -- In our component-based development methodology, each developer is responsible for ensuring that the software he or she creates is easy to understand and use, and not especially easy to misuse. One common form of misuse is to invoke a library function or method under circumstances where not all of its preconditions are satisfied, leading to undefined behavior. Contracts having undefined behavior are not necessarily undesirable, and (for many engineering reasons) are often optimal. Most would agree that a well-implemented library should do something other than silently continue when a pre-condition violation is detected, although these same folks might not agree on what specific action should be taken. Unfortunately, validating preconditions implies writing additional code that will execute at runtime. More code runs slower, and some would fairly argue that they should not be forced to pay for redundant runtime checks in the library software they use. Whether and to what extent library functions should validate their preconditions, and what should happen if a precondition violation is detected are questions that are best answered on an application by application basis - i.e., by the owner of main. "Defensive Programming Done Right" makes it all possible. In this talk, we begin by reviewing the basic concepts of Design-By-Contract (DbC), and what we mean by the term "Defensive Programming" (DP). We then explore our overall approach to institutionalizing defensive programming in robust reusable library software such that each application can conveniently specify both the runtime budget (e.g., none, some, lots) for defensive checking, and also the specific action to be taken (e.g., abort, throw, spin) should a precondition violation occur. Along the way, we touch on how modern compilers and linkers work, binary compatibility, and the consequences of possibly violating the one-definition rule in mixed-mode builds. We conclude the talk by describing and then demonstrating our "negative testing" strategy (and supporting test apparatus) for readily verifying, in our component-level test drivers, that our defensive checks detect and report out-of-contract client use as intended. Actual source for the supporting utility components will be presented throughout the talk and made available afterwards. -- John Lakos, author of "Large Scale C++ Software Design.", serves at Bloomberg LP in New York City as a senior architect and mentor for C++ Software Development world-wide. He is also an active voting member of the C++ Standards Committee, Library Working Group. Previously, Dr. Lakos directed the design and development of infrastructure libraries for proprietary analytic financial applications at Bear Stearns. For 12 years prior, Dr. Lakos developed large frameworks and advanced ICCAD applications at Mentor Graphics, for which he holds multiple software patents. His academic credentials include a Ph.D. in Computer Science ('97) and an Sc.D. in Electrical Engineering ('89) from Columbia University. Dr. Lakos received his undergraduate degrees from MIT in Mathematics ('82) and Computer Science ('81). His next book, entitled "Large-Scale C++, Volume I: Process and Architecture", is anticipated in 2014. -- Videos Filmed & Edited by Bash Films: http://www.BashFilms.com *-----* Register Now For CppCon 2022: https://cppcon.org/registration/ *-----*

Самый важный алгоритм в истории [Veritasium]

Если вы в России: https://boosty.to/vertdider Если вы не в России: https://www.patreon.com/VertDider Учёные открыли быстрое преобразование Фурье, всего на пару лет опоздав к запрету испытаний ядерного оружия. Если бы они успели, запрет был бы строже и в мире не появилось бы столько ядерных бомб. Обиднее всего, что всё необходимое для открытия в свои записи занёс Гаусс за 150 лет до этого. В лучших традициях видео Дерека Маллера, из этого видео узнаем, какой алгоритм помогает нам смотреть картинки в интернете, а в середине XX века мог остановить ядерную гонку. Перевод: Елена Смотрова Редактура: Алексей Малов Научная редактура: Михаил Столповский Озвучка: Дмитрий Чепусов Монтаж звука: Андрей Фокин Монтаж видео: Джон Исмаилов Обложка: Андрей Гавриков Спасибо за поддержку на https://www.patreon.com/VertDider и https://boosty.to/vertdider Озвучки Vert Dider выходят с вашей помощью: Pavel Dunaev, Mikhail Stolpovskiy, Sergey Zhukov, Ira Kozlovskaya, Amir, Ника Калмыкова, Куляш, Roman Inflianskas, Мikhail Samin, Aleksandr P., Vitaliy Vachynyuk, Andrei Lubalin, Pavel Parpura, Anton Bolotov, Alena, opperatius, Oleg Zingilevskiy, Eugene Tsaplin, Anatoly Ressin, Katoto Chan, angel, Kirill Zaslavskii, Victor Cazacov, David Malko, Vadim Velicodnii, Artem Amirbekov, Dzmitryi Halyava, Nastya, Stanislav Obrazcoff, POD666, Evgeny Vrublevsky, Alexander Balynskiy, Oleksandr Hrebeniuk, Ilya, Vladyslav Sokolenko, Kseniya Stukova, Валентин Матвейчик, Irina Shakhverdova, Leonid Steinberg, Kirill Vedensky, Aleksei Shabalin, Alexander Goida, Katya Ma, Morock_D, Sergey P, Ranis Zaripov Roman Gelingen, Сергей Клопов, Alexander Lebedev, Lexx, Nikrodol, Rincewind, Sonra44, Rashn, Rashn, Адам Шифф, Владимир Ямщиков, Мария Зверева, Валентин Ильин, Сергей Платоненко, Anton G, Dmitry Perekalin, Vadim, Владимир Авдиев, MaximML , Rekvet, Timophey Popov, Timur Rahmatulin, Timur Rahmatulin, Адам Шифф, Арс Ник, Иван Новиков, Илья Зверев, Никита Омельницкий, Ranis Zaripov #VertDider #Veritasium Сайт студии: http://vertdider.tv Мы в социальных сетях: — http://vk.com/studio_vd — https://t.me/vertdider — https://twitter.com/Vert_Dider — http://coub.com/vertdider Разрешение на публикацию: https://bit.ly/2SFhrHZ © https://www.youtube.com/c/veritasium/ Источник: https://youtu.be/nmgFG7PUHfo