🌘 C++ RAII 與錯誤處理的兩難：從 Bjarne 的範例談起
➤ 探索 C++ RAII 與錯誤處理的精妙平衡
✤ https://marler8997.github.io/blog/bjarne-fix-your-language/
本文深入探討 C++ 中資源獲取即初始化（RAII）與例外處理機制在實際應用中的潛在問題，特別是當操作可能失敗時。作者以 Bjarne Stroustrup 展示的 C++ 檔案開啟範例為引，說明 RAII 雖能確保資源釋放，但在處理檔案開啟失敗等常規錯誤時，若依賴例外處理，可能導致訊息不準確、例外捕獲不完全，以及資源獲取在第二次初始化（RAISI）的複雜性。文章對比了 C 語言以返回值處理錯誤的直觀性，並提出瞭解決 C++ RAII 相關錯誤處理問題的兩種方法：一是在建構子外進行可能失敗的操作，二是採用類似 `std::error_code` 的「側通道」機制，以期在保留 RAII 優勢的同時，提升錯誤處理的清晰度和可靠性。
+ 這篇文章讓我對 C++ 的例外處理有了更深的認識，尤其是在檔案操作
#C++ #RAII #錯誤處理 #程式設計

Inside of an actor, we can't assume `deinit` is isolated. If anything, we ought to assume the opposite.

Since there's no easy way to express "release all owned resources", the actual change I'm being nudged towards is: express ONLY resource ownership with a new type. There, you can use deinit.

This is #RAII from C++, but in Swift.

Modern C++ – RAII

https://green7ea.github.io/modern/modern.html

#HackerNews #ModernC++ #RAII #C++Programming #SoftwareDevelopment #CodingBestPractices

[Перевод] Линус Торвальдс: Критика C++ — Комплексный анализ

Линус Торвальдс, создатель (и великодушный диктатор) Linux, всегда с особой критикой относился к C++, объясняя почему он отвергает его в разработке ядра Linux. Но он не просто резко высказывается против использования C++, а приводит ряд аргументов, которые мы с вами сегодня и рассмотрим.

https://habr.com/ru/companies/otus/articles/902724/

#c++ #linux #Линус_Торвальдс #ядро_Linux #исключения_в_c++ #RAII #управление_памятью #ооп #абстракции_в_программировании

RAII 2.0: RAII как архитектурный инструмент в C++

Идиома RAII — давно зарекомендовал себя как удобный способ автоматического управления ресурсами в C++. Обычно мы применяем его для управления памятью, файловыми дескрипторами или мьютексами. Однако что, если расширить понятие RAII до управления не только физическими ресурсами, но и логическими контрактами и состояниями системы? В этой статье я хочу поговорить о том, как RAII можно использовать для контроля жизненного цикла асинхронных операций, транзакций или подписок, гарантируя их корректное завершение или откат до прежнего состояния.

https://habr.com/ru/articles/901092/

#С++ #RAII #Жизненный_цикл #Подписки #Транзакции #Безопасность_кода #управление_ресурсами #паттерны #Логический_контракт

Understanding Memory Management, Part 2: C++ and RAII — https://educatedguesswork.org/posts/memory-management-2/
#HackerNews #MemoryManagement #C++ #RAII #ProgrammingTips #TechInsights #EducatedGuesswork

The #Zig guys wade into the #Rust in the #Linux kernel brouhaha:

“RAII And The Rust/Linux Drama”, Loris Cro (https://kristoff.it/blog/raii-rust-linux/).

On HN: https://news.ycombinator.com/item?id=42291417

On Lobsters (where Asahi Lina responds): https://lobste.rs/s/hxerht/raii_rust_linux_drama

#RAII #SystemsProgramming #OSDev

Man, I wish Rust had the 'defer' keyword 😞
Wait...

🦀 **scopeguard**: A Rust library for a convenient RAII scope guard.

🌀 Has a defer! macro.

🔥 Runs a closure on scope exit, even if a panic occurs.

⭐ GitHub: https://github.com/bluss/scopeguard

#rustlang #library #defer #scope #raii #guard #programming #pattern #opensource

C++OnSea 2024 SESSION ANNOUNCEMENT: The Surprising Power of Small Wrapper Classes by Jørgen Fogh

https://cpponsea.uk/2024/sessions/the-surprising-power-of-small-wrapper-classes

Register now at https://cpponsea.uk/tickets/

#wrappers #softwaredesign #RAII #cpp #cplusplus

C++OnSea 2024 SESSION ANNOUNCEMENT: The Surprising Power of Small Wrapper Classes by Jørgen Fogh

https://cpponsea.uk/2024/sessions/the-surprising-power-of-small-wrapper-classes

Register now at https://cpponsea.uk/tickets/

#wrappers #softwaredesign #RAII #cpp #cplusplus

Having worked a few weeks now with #C #code that uses __attribute__ (cleanup) , I am disappointed to say that it's an insignificant improvement.

Why?

Because you need to remember to annotate every variable, and sometimes cleanup is not what you want, leading to double-free.
At least the freeing is declared next to the variable, so that's nice.

But this still sucks compared to #RAII imposed on the type, where you don't need to remember.

#programming #coding #memory #safety

Resource acquisition is initialization.

Her blir det liv.

#raii #raii

We have released a new CppCon 2023 Video!

Coroutine Patterns: Problems and Solutions Using Coroutines in a Modern Codebase – Francesco Zoffoli
https://youtu.be/Iqrd9vsLrak
#BestPractices #Compilers #Coroutines #cpp #FollyLibrary #Idioms #RAII

Blogged: Use Scope Guards to Prevent Resource Leaks

Modern #C++ has many neat #RAII-based solutions for managing resources. However, every now and then one needs to manually make sure that some code is run when a resource is not needed anymore. One great solution to this problem is a #ScopeGuard. I've surprisingly rarely seen them used in practice!

https://www.lukas-barth.net/blog/scope-guards-resource-leaks/?s=fv

#cpp #cplusplus

(Note: Replies to this post will be visible as comments on the blog.)

@jaredwhite Yeah I am wondering if it would make more sense to have a separate community protocol for initialization.

I'm very strongly of the opinion that you should never be able to get a reference to an uninitialized object (I think this is sometimes called #RAII?) Unfortunately that ship sailed for web components a long time ago. Constructors are worthless in this context too (and terrible per https://blog.dwac.dev/posts/ctor/). So maybe a protocol around initialization would help, whether that is or isn't `defer-hydration`.

@jhx You asked for it, so I'll answer it:

Imho, C++ design is broken from the very beginning. It wanted to provide #OOP language constructs, still maintaining full #C compatibility (which already failed many years ago, cause the languages took different roads).

It combines #exceptions (IMHO generally a bad idea) with explicit resource management (an *awful* idea, forcing you to use #RAII which will in turn mandate creation of purely "technical" classes, just to manage resources).

It wanted #generics, but that's impossible without breaking C compatibility, so it came up with #templates, actually a #preprocessor on steroids.

Overloading also doesn't fit into the simple C library ABI (where #linker symbols are named just like the function), so it came up with "name mangling" ... which is especially horrific because it is *not* standardized.

Ah well, I could go on 😂

As much as we love #C, we've always felt the lack of a convenient #RAII feature in the language. Yet, many compilers allow to implement such feature with relatively little effort.

So, @micia thought to share such implementation, and our point of view on the subject, in a article.

We’ll be glad to hear your feedback and suggestions before we publish it on our website.

#CProgramming #Programming #software

https://codeberg.org/1414codeforge/articles/src/branch/main/drafts/structured-resource-management-in-c/article.md

Il #C ci piace, ma sentiamo spesso la mancanza di un meccanismo di #RAII nel linguaggio. Per fortuna, molti compilatori consentono di implementarne uno con relativamente poco sforzo.

Perciò il buon @micia ha pensato di buttare giù un articolo per mostrare come farlo e spiegare il nostro punto di vista.

Qualcuno abbastanza volenteroso da condividere commenti e dirci se abbiamo sbagliato nulla, prima di pubblicarlo sul nostro sito?

#CProgramming #Programming

https://codeberg.org/1414codeforge/articles/src/branch/main/drafts/structured-resource-management-in-c/article.md

Une nef en roseaux pour traverser la Méditerranée sur les traces des Egyptiens https://www.lexpress.fr/actualites/1/actualite/une-nef-en-roseaux-pour-traverser-la-mediterranee-sur-les-traces-des-egyptiens_2092398.html - Thor Heyerdal l'avait déjà fait. #KonTiki #RaII