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@@ -26,6 +26,7 @@ RSS使用仓库的release RSS [链接](https://github.com/wanghenshui/cppweeklyn
 | [二十一](./posts/021.md) | [二十二](./posts/022.md) | [二十三](./posts/023.md) | [二十四](./posts/024.md) | [二十五](./posts/025.md) | [二十六](./posts/026.md) | [二十七](./posts/027.md) | [二十八](./posts/028.md) | [二十九](./posts/029.md) | [三十期](./posts/030.md) |
 | [三十一](./posts/031.md) | [三十二](./posts/032.md) | [三十三](./posts/033.md) | [三十四](./posts/034.md) | [三十五](./posts/035.md) | [三十六](./posts/036.md) | [三十七](./posts/037.md) | [三十八](./posts/038.md) | [三十九](./posts/039.md) | [四十期](./posts/040.md) |
 | [四十一](./posts/041.md) | [四十二](./posts/042.md) | [四十三](./posts/043.md) | [四十四](./posts/044.md) | [四十五](./posts/045.md) | [四十六](./posts/046.md) | [四十七](./posts/047.md) | [四十八](./posts/048.md) | [四十九](./posts/049.md) | [五十期](./posts/050.md) |
+| [五十一](./posts/051.md) |  |  |  |  |  |  |  |  |  |
 
 
 

diff --git a/posts/050.md b/posts/050.md
@@ -27,7 +27,7 @@ c++ summit在上海要开，三月份，两天套票接近六千，真心贵，
 
 ## 文章
 
-- [**Did you know that C++23 added Attributes on Lambda-Expressions?**](https://github.com/QuantlabFinancial/cpp_tip_of_the_week/)
+- [**Did you know that C++23 added Attributes on Lambda-Expressions?**](https://github.com/QuantlabFinancial/cpp_tip_of_the_week/blob/master/265.md)
 
 ```c++
 constexpr auto foo = [] [[deprecated]] { };

diff --git a/posts/051.md b/posts/051.md
@@ -0,0 +1,249 @@
+---
+layout: post
+title:  第51期
+---
+
+# C++ 动态新闻推送 第51期
+
+从[reddit](https://www.reddit.com/r/cpp/)/[hackernews](https://news.ycombinator.com/)/[lobsters](https://lobste.rs/)/[meetingcpp](https://www.meetingcpp.com/blog/blogroll/items/Meeting-Cpp-Blogroll-318.html/)摘抄一些c++动态
+
+[周刊项目地址](https://github.com/wanghenshui/cppweeklynews)｜[在线地址](https://wanghenshui.github.io/cppweeklynews/) ｜[知乎专栏](https://www.zhihu.com/column/jieyaren) |[腾讯云+社区](https://cloud.tencent.com/developer/column/92884)
+
+弄了个qq频道，[手机qq点击进入](https://qun.qq.com/qqweb/qunpro/share?_wv=3&_wwv=128&inviteCode=xzjHQ&from=246610&biz=ka)
+
+欢迎投稿，推荐或自荐文章/软件/资源等，请[提交 issue](https://github.com/wanghenshui/cppweeklynews/issues)
+
+---
+
+## 资讯
+
+标准委员会动态/ide/编译器信息放在这里
+
+[标准委员会二月份邮件列表](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2022/#mailing2022-02)
+
+推荐阅读 [C++ exceptions are becoming more and more problematic](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2022/p2544r0.html)
+
+异常，太坑了
+
+[编译器信息最新动态推荐关注hellogcc公众号 本周更新 2022-02-23 第138期](https://github.com/hellogcc/osdt-weekly/blob/master/weekly-2022/2022-02-23.md)
+
+
+
+## 文章
+
+- [Linux's getrandom() Sees A 8450% Improvement With Latest Code](https://git.kernel.org/pub/scm/linux/kernel/git/crng/random.git/log/)
+
+替换了算法，使用black而不是sha1
+
+- [Chrome V8 源码 解读系列](https://www.zhihu.com/people/v8blink/posts)
+
+这个人写了很多文章。对浏览器感兴趣的/业界人士可以关注一波。我不太懂就不多说了
+
+- [My favorite C++20 feature](https://schneide.blog/2022/02/21/my-favorite-c20-feature/)
+
+这玩意, 确实挺方便
+
+```c++
+auto request = http_request{
+  .method = http_method::get,
+  .uri = "localhost:7634",
+  .headers = { { .name = "Authorization", .value = "Bearer TOKEN" } },
+};
+```
+
+- [c++反射深入浅出 - 1. ponder 反射实现分析总篇](https://zhuanlan.zhihu.com/p/471396674)
+- [c++反射深入浅出 - 2. property 实现分析](https://zhuanlan.zhihu.com/p/472265782)
+
+解析ponder这个库。对于想学习反射的值得一看
+
+- [A Good Way to Handle Errors Is To Prevent Them from Happening in the First Place](https://www.fluentcpp.com/2022/02/25/a-good-way-to-handle-errors-is-to-prevent-them-from-happening-in-the-first-place/)
+
+尽可能把错误处理掉或者用optional /expect / outcame包装处理掉
+
+- [Returning values and errors](https://rachelbythebay.com/w/2022/02/20/return/)
+
+```c++
+string* UserIP(); //1
+string UserIP(string* errmsg); //2
+bool GetUserIP(string* ip); //3
+bool GetUserIP(string* ip, string* errmsg); //4
+Result<string> UserIP(); //5
+ResultString UserIP(); //6
+string UserIP(); //7
+```
+
+大家觉得哪个接口好？
+
+1肯定不行，2 3 4都需要传进个string处理，比较脏， 5是不是太复杂了，6是简单版本，但是会不会又有ResultDouble之类的东西？7简单，只有ip，errmsg不放进去，也许这个才是最优解？
+
+开放题，没有答案
+
+- [Implementing the FLIP algorithm](https://www.jeremyong.com/color%20theory/2022/02/19/implementing-the-flip-algorithm/)
+
+图形学的东西，不太懂，这里标记TODO
+
+- [Ways to Refactor Toggle/Boolean Parameters in C++](https://www.cppstories.com/2017/03/on-toggle-parameters/)
+
+```c++
+DoImportantStuff(true, false, true, false);
+```
+
+我们都知道这种参数会有莫名其妙的问题，丢失值的信息，一个两个倒还好，多了难免眼花，怎么重构，封装成enum
+
+```c++
+enum class UseCacheFlag    { False, True };
+enum class DeferredFlag    { False, True };
+enum class OptimizeFlag    { False, True };
+enum class FinalRenderFlag { False, True };
+
+// and call like:
+RenderGlyphs(glyphs,
+             UseCacheFlag::True, 
+             DeferredFlag::False, 
+             OptimizeFlag::True, 
+             FinalRenderFlag::False);
+```
+
+使用bit flag
+
+```c++
+#include <type_traits>
+
+struct Glyphs { };
+
+enum class RenderGlyphsFlags
+{
+    useCache = 1,
+    deferred = 2, 
+    optimize = 4,
+    finalRender = 8,
+};
+
+// simplification...
+RenderGlyphsFlags operator | (RenderGlyphsFlags a, RenderGlyphsFlags b) {
+    using T = std::underlying_type_t <RenderGlyphsFlags>;
+    return static_cast<RenderGlyphsFlags>(static_cast<T>(a) | static_cast<T>(b));
+    // todo: missing check if the new value is in range...
+}
+
+constexpr bool IsSet(RenderGlyphsFlags val, RenderGlyphsFlags check) {
+    using T = std::underlying_type_t <RenderGlyphsFlags>;
+    return static_cast<T>(val) & static_cast<T>(check);
+    // todo: missing additional checks...
+}
+
+void RenderGlyphs(Glyphs &glyphs, RenderGlyphsFlags flags)
+{
+    if (IsSet(flags, RenderGlyphsFlags::useCache)) { }
+    else { }
+
+    if (IsSet(flags, RenderGlyphsFlags::deferred)) { }
+    else { }
+
+    // ...
+}
+
+int main() {
+    Glyphs glyphs;
+    RenderGlyphs(glyphs, RenderGlyphsFlags::useCache | RenderGlyphsFlags::optimize);                                      
+}
+
+```
+
+结构体
+
+```c++
+struct RenderGlyphsParam
+{
+    bool useCache;
+    bool deferred;
+    bool optimize;
+    bool finalRender;
+};
+void RenderGlyphs(Glyphs &glyphs, const RenderGlyphsParam &renderParam);
+
+// the call:
+RenderGlyphs(glyphs,
+             {/*useCache*/true, 
+             /*deferred*/false, 
+             /*optimize*/true, 
+             /*finalRender*/false});
+
+```
+
+c++20我们有了字段构造，字段信息终于有了
+
+```c++
+struct RenderGlyphsParam
+{
+    bool useCache;
+    bool deferred;
+    bool optimize;
+    bool finalRender;
+};
+void RenderGlyphs(Glyphs &glyphs, const RenderGlyphsParam &renderParam);
+
+// the call:
+RenderGlyphs(glyphs,
+             {.useCache = true, 
+              .deferred = false, 
+              .optimize = true, 
+              .finalRender = false}); 
+
+```
+
+这个更完美一些
+
+- [Supervising in C++: how to make your programs reliable](https://basiliscos.github.io/blog/2022/02/20/supervising-in-c-how-to-make-your-programs-reliable/) 
+
+介绍c++一些Supervise管理策略以及actor框架使用，比较少用。基本上都是糊一个taskflow模型，不用什么let it crash。这种东西放在背后的管理系统来做。不在业务进程里做
+
+## 视频
+
+- [C++ Weekly - Ep 312 - Stop Using `constexpr` (And Use This Instead!) ](https://www.youtube.com/watch?v=4pKtPWcl1Go)
+
+constexpr修饰函数，没问题
+
+constexpr修饰值，这个值未必是编译期计算(用const可以)，取决于编译器，且 constexpr修饰的值肯定在堆栈，所以要注意作用域问题 
+
+- [Keynote: C++'s Superpower - Matt Godbolt - CPPP 2021](https://www.youtube.com/watch?v=0_UttFDnV3k)
+
+介绍周边生态
+
+- [Introduction to memory exploitation - Patricia Aas - Meeting C++ 2021](https://www.youtube.com/watch?v=s18lHhN-NXc)
+
+讲fuzzer的工作原理
+
+- [Design of a C++ reflection API - Matúš Chochlík - Meeting C++ online](https://www.youtube.com/watch?v=BP0gsVy502w)
+
+介绍他写的一个反射库
+
+- [The Basics of Profiling - Mathieu Ropert - CppCon 2021](https://www.youtube.com/watch?v=dToaepIXW4s)
+
+没啥意思。讲window profile的
+
+- [Design and Implementation of Highly Scalable Quantifiable Data Structures in C++ - CppCon 2021](https://www.youtube.com/watch?v=ECWsLj0pgbI&list=PLHTh1InhhwT6vjwMy3RG5Tnahw0G9qIx6&index=74)
+
+这讲的是个啥啊？论文在Parallel Computing Technologies这本书里，谁能搞个电子版，原版太贵了。愣是没听明白。这里标记TODO，有机会再看吧
+
+## 开源项目需要人手
+
+- [asteria](https://github.com/lhmouse/asteria) 一个脚本语言，可嵌入，长期找人，希望胖友们帮帮忙，也可以加群384042845和作者对线
+- [pika](https://github.com/OpenAtomFoundation/pika) 一个nosql 存储， redis over rocksdb，非常需要人贡献代码胖友们， 感兴趣的欢迎加群294254078前来对线
+
+## 新项目介绍/版本更新
+
+- [raw pdb](https://github.com/MolecularMatters/raw_pdb) c++17一个解析pdb的库
+- [ledit](https://github.com/liz3/ledit) 一个编辑器
+- [HFSM2 development might slow down](https://www.reddit.com/r/cpp/comments/t0od6u/hfsm2_development_might_slow_down/) 乌克兰正在打仗，作为当地人无心工作
+- [thread-pool](https://github.com/DeveloperPaul123/thread-pool) 又一个线程池实现
+
+实现线程池我们真正需要的是什么？是一个干活线程还是任务的投递/管理？纯纯一个线程池轮子也就看看，用处不大
+
+## 工作招聘
+
+---
+
+看到这里或许你有建议或者疑问或者指出错误，请留言评论! 多谢!  你的评论非常重要！也可以帮忙点赞收藏转发！多谢支持！
+
+[本文永久链接](https://wanghenshui.github.io/cppweeklynews/posts/051.html)