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@@ -26,7 +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) | [五十二](./posts/052.md) | [五十三](./posts/053.md) |  [五十四](./posts/054.md)| [五十五](./posts/055.md) | [五十六](./posts/056.md) | [五十七](./posts/057.md) | [五十八](./posts/058.md) |  |  |
+| [五十一](./posts/051.md) | [五十二](./posts/052.md) | [五十三](./posts/053.md) |  [五十四](./posts/054.md)| [五十五](./posts/055.md) | [五十六](./posts/056.md) | [五十七](./posts/057.md) | [五十八](./posts/058.md) | [五十九](./posts/059.md) |  |
 
 
 

diff --git a/posts/059.md b/posts/059.md
@@ -0,0 +1,259 @@
+---
+layout: post
+title:  第59期
+---
+
+# C++ 动态新闻推送 第59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-326.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
+
+[编译器信息最新动态推荐关注hellogcc公众号 本周更新2022-04-20 第146期](https://github.com/hellogcc/osdt-weekly/blob/master/weekly-2022/2022-04-20.md)
+
+## 文章
+
+- [**Did you know about C++23 proposal `Structured Bindings can introduce a Pack`?**](https://github.com/QuantlabFinancial/cpp_tip_of_the_week/blob/master/274.md)
+
+```c++
+#include <tuple>
+#include <cassert>
+
+int main() {
+  auto [first, ...ts] = std::tuple{1, 2 ,3};
+  assert(1 == first);
+}
+```
+
+看个乐。提案中
+
+- [The infamous bug of range-based for loops](https://www.sandordargo.com/blog/2022/04/20/range-base-p2012)
+
+```c++
+#include <iostream>
+#include <string>
+#include <vector>
+
+std::vector<std::string> createStrings() {
+    return {"This", "is", "a", "vector", "of", "strings"};
+}
+
+int main()
+{
+  for (auto w: createStrings()) {
+      std::cout << w << " "; // this works fine
+  }
+  std::cout << std::endl;
+  for (auto c: createStrings()[0]) {
+      std::cout << c << " "; // this is UB
+  }
+  std::cout << std::endl;
+}
+```
+
+经典bug :range for里面的变量生命周期有问题
+
+聪明的你想到了用optional，照样不行
+
+```c++
+#include <iostream>
+#include <optional>
+#include <string>
+#include <vector>
+
+std::vector<std::string> createStrings() {
+    return {"This", "is", "a", "vector", "of", "strings"};
+}
+
+std::optional<std::vector<int>> createOptionalInts() {
+    return std::vector<int>{1,2,3,4,5,6};
+}
+
+
+int main()
+{
+  for (auto i: createOptionalInts().value()) {
+      std::cout << i << " "; // UB
+  }
+  const auto v = createOptionalInts().value(); //注意，必须是值，写成const auto& 一样是UB
+  for (auto i: v) {
+      std::cout << i << " ";
+  }
+  std::cout << std::endl;
+}
+//0 0 27344912 0 5 6 1 2 3 4 5 6 
+```
+
+其实range for是语法糖，上面的代码等价于
+
+```c++
+#include <iostream>
+#include <optional>
+#include <string>
+#include <vector>
+
+std::optional<std::vector<int>> createOptionalInts() {
+    return std::optional<std::vector<int>>1;
+}
+
+int main()
+{  
+  auto&& range = createOptionalInts().value();
+  auto position = range.begin();
+  auto end = range.end();
+  for(; position != end; ++position) {
+      std::cout << *(position) << " "; // UB
+  }
+  std::cout << std::endl; 
+}
+```
+
+问题就在这个range已经消失了，访问这个指针就有问题
+
+- [How can I `co_await` on a Windows Runtime async action or operation with a timeout?](https://devblogs.microsoft.com/oldnewthing/20220415-00/?p=106486)
+
+有点看不懂了
+
+```c++
+auto timedOut = std::make_shared<bool>();
+auto widgetOperation = GetWidgetAsync();
+auto widgetTimeout = [](auto timedOut) -> IAsyncOperation<Widget>
+    {
+        co_await winrt::resume_after(15s);
+        *timedOut = true;
+        co_return nullptr;
+    }(timedOut);
+auto widget = co_await winrt::when_any(widgetOperation, widgetTimeout);
+
+widgetOperation.Cancel();
+widgetTimeout.Cancel();
+
+if (*timedOut) {
+    // timed out
+} else {
+    // GetWidgetAsync() produced something (possibly nullptr)
+}
+
+```
+
+```c++
+auto widgetOperation = GetWidgetAsync();
+auto widgetTimeout = [] -> IAsyncOperation<Widget>
+    {
+        co_await winrt::resume_after(15s);
+        co_return nullptr;
+    }();
+auto widget = co_await winrt::when_any(widgetOperation, widgetTimeout);
+auto timedOut = widgetTimeout.Status() == AsyncStatus::Completed;
+
+widgetOperation.Cancel();
+widgetTimeout.Cancel();
+
+if (timedOut) {
+    // timed out
+} else {
+    // GetWidgetAsync() produced something (possibly nullptr)
+}
+```
+
+- [Class template argument deduction may be the new hotness, but we’ll always have maker functions](https://devblogs.microsoft.com/oldnewthing/20220420-00/?p=106506)
+
+CTAD把活交给了编译器推导，但大家没咋用，还是有make_xx函数来构造对象，清晰，明确
+
+- [Multi-GPU Programming with Standard Parallel C++, Part 1](https://developer.nvidia.com/blog/multi-gpu-programming-with-standard-parallel-c-part-1/)
+- [Multi-GPU Programming with Standard Parallel C++, Part 2](https://developer.nvidia.com/blog/multi-gpu-programming-with-standard-parallel-c-part-2/)
+
+`nvc++ compiler`软文的感觉。介绍了一些算法可以并行，比如
+
+```c++
+// Step 1: compute the number of variables contributed by every node.
+int* numValuesPtr = allocateMemory(numberOfCells);
+for_each(execution::par_unseq, numValuesPtr,
+         numValuesPtrl + numberOfCells, [=](int& numValues)
+{
+    int i = &numValues - numValuesPtr;
+    // Compute number of variables contributed by current node.
+    numValues = computeNumValues(i);
+} );
+// 2. Compute the buffer index for every node.
+int* indexPtr = allocateMemory(numberOfCells);
+exclusive_scan(execution::par_unseq, numValuesPtr,
+         numValuesPtr + numberOfCells, indexPtr, 0);
+// 3. Pack the data into the buffer.
+for_each(execution::par_unseq, indexPtr,
+         indexPtr + numberOfCells, [=](int& index)
+{
+    int i = &index - indexPtr;
+    packCellData(i, index);
+} );
+```
+
+
+
+- [Faster GDB Startup](https://tromey.com/blog/?p=1084)
+
+介绍gdb启动都做了什么以及如何优化启动速度
+
+- [What’s new for C++ Debugging in Visual Studio Code](https://devblogs.microsoft.com/cppblog/whats-new-for-c-debugging-in-visual-studio-code/?WT.mc_id=academic-0000-abartolo)
+
+介绍vscode更新的调试功能（谁用vscode调试啊）
+
+## 视频
+
+- [C++ Weekly - Ep 320 - Using `inline namespace` To Save Your ABI ](https://www.youtube.com/watch?v=rUESOjhvLw0)
+
+```c++
+namespace tool {
+inline namespace v1_0_0 {
+struct Data {
+  int a;
+  bool b;
+  std::string c;
+};
+bool foo(const Data d);
+}
+}
+
+int main() {
+  const tool::Data d;
+  return tool::foo(d);
+}
+```
+
+看到这个用法，inline namespace在调用的时候可以省掉，但是这个inline namespace的符号可以保证唯一，这样就避免了不同版本造成的ABI break
+
+很妙，但没人用。这属于项目管理的一部分。严格来说很难出现ABI break
+
+
+
+## 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
+
+- [mleak](https://github.com/mini-rose/mleak) 劫持malloc/free 分析内存泄漏
+- [boostdep-report](https://pdimov.github.io/boostdep-report/) 分析boost各个组件的依赖关系 比如asio依赖boost core之类的
+- [vcpkg April 2022 Release is Now Available](https://devblogs.microsoft.com/cppblog/vcpkg-april-2022-release-is-now-available/)
+- [poco Release 1.11.2 Available](https://pocoproject.org/blog/?p=1156)
+
+## 工作招聘
+
+互联网寒冬了胖友们
+
+---
+
+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/059.html)