Agenda  Compile-Time Rational Numbers  Durations  Clocks  Time Points  Dates  Time Zones 4 Agenda  Compile-Time Rational Numbers  Durations  Clocks  Time Points   Dates  Time Zones5 Compile-Time Rational Numbers  Defined in  Work with rational numbers at compile time  Always normalized representation  Needed for durations in the library6 library6 Compile-Time Rational Numbers  Define a rational number: using r1 = ratio<1, 60>; // Represents 1/60  Retrieve numerator and denominator intmax_t num { r1::num }; intmax_t den { r1::den

Gela Malek Pour gmalekpour@esri.com Visualize Time Enabled Data using ArcGIS Qt (C++) and ToolkitAbout Esri • We build mapping technology that our customers use to solve the world’s most complex challenges around the worldPurpose of this talk • Showcase a quick way to create a desktop app to visualize time enabled data • Setup the development environment using Esri templates • Use the ArcGIS toolkit to feature layer that include hurricane data as features • Each feature has a specific start time and end time in the feature table • We will use these start and end date values to draw and clear features

Go 读书会第二期 白明 《 Go 语言精进之路》作者 tonybai.com 博主 目 录 写书的历程 0 1 Go 语言精进之路导读 0 2 我是怎么读书的 0 3 写书的历程 第一部分 程序员的“小目标”与写书三要素 写书三要素 写书 <- 能力 +意愿 + 机会 过程 写书不易，写高质量的书更难 2018 年下 旬开始动笔 2020 年 11 月下旬 初稿交付 初稿交付 2021 年 12 月出版 《 Go 语言精进之路》导读 第二部分 整体写作思路 异曲同工 精进之路，思维先行 – part1 践行哲学，遵循惯例，认清本质，理解原理 - (part2- part10) 精进之路，思维先行 异曲同工 “ 语言决定思维方式” - 萨丕尔假说 “ 我的语言之局限，即我的世界之局限” - 路德维 希 · 维特根斯坦（语言哲学奠基人） “ - Alan Perlis ( 首届图灵奖得主 ) Part1 - 进入 Go 语言编程思维导引 站在语言设计者的高度理解 Go 的与众不同 Go 诞生 与演进 Go 设计哲 学 Go 编程思 维举例 怎么学习 Go 思维？ 学习本质是一种模仿。要学习 Go 思维，就要 去模仿 go 团队、 go 社区的优秀项目和代 码，看看他们怎么做的 践行哲学，遵循惯例，认清本质，理解原理

cargo build —target wasm- unknown-unknown waPC Host (Go) waPC Guest Rust • Read wasm file • Select engine • Wazero • Wasmer-go • Wasmertime-go • Define hostcall capability • Instantiate • Invoke - maintenance due to programming language 大公司 API 测试的需求 软件测试工具 • 模拟数据规则 • 自动化测试 • Use rust to compile wasm and send to wasm mock server • Let Wasm Mock Server send http request • 升级平台能解决不一致的问题 of its’ Host call • http request • Tcp Request • Tcp Response • Redis • GET • SET • Memcache • Time • Sleep • now websocket standin for wasm • 可用 Javascript 在游览器里面 模拟数据 • 发 RPC 请求 • 可以上传 proto

Invoke (P/Invoke), COM interop, C++/CLI – 2002, 2005 JVM – Java Native Access (JNA) – 2007 Go – cgo – permit C in the .go source file – 2009 Swift – share a runtime and be like C – 2014There is no one approach and clang, sizeof(long) == sizeof(size_t) MSVC, sizeof(long) == 4 Cygwin compile of gcc, sizeof(long) == sizeof(size_t) MSYS2 compile of gcc, sizeof(long) == 4You can make interop suck less by… Explicitly

numberOfValues) { for (int i { startValue }; i < startValue + numberOfValues; ++i) { time_t t { system_clock::to_time_t(system_clock::now()) }; cout << std::ctime(&t); co_yield i; } } int main() 12:00Concepts20 Concepts  Named requirements to constrain template parameters  Predicates evaluated at compile time21 Concepts  Example of a concept definition: template concept Incrementable = atomic_shared_ptr head; // in C++11: remove "atomic_" and use special // functions every time you touch head public: class reference { shared_ptr p; }; auto find(T

in_range(T t) noexcept;11 constexpr Algorithms12 C++20 constexpr Everything • constexpr enables compile-time programming without arcane templates • Algorithms: • P0202R3 constexpr And exchange() Example: lookup tables • Everyone uses lookup tables • Arrays are maximally space-efficient, very time-efficient • Sorted arrays: binary_search, lower_bound, equal_range • Now you can use constexpr algorithms • More advanced: constexpr sort your lookup tables14 static_assert is_sorted • Compile-time evaluation = no run-time codegen, even in debug builds #include #include #include

test that your code is appropriately marked constexpr. • Add tests that execute at compile time and fail to compile if the test fails. This ensures: – You do not call a non-constexpr function from a • May improve performance by: • Moving work from runtime to compile time. • Making dimensions of vectors/matrices available at compile time. 49 |Concluding RemarksAustralia’s National Science Agency

g. 2019, 2017) Step #2: Compile your code (with the same compiler as today) 💡 MSVC 2015, 2017 and 2019 toolsets are available directly from Visual Studio 2022 Step #3: Compile your code with the latest compatibility between the VS2022 and previous C++ runtimes (VS 2019, VS 2017, VS 2015) Step #4: Compile your dependencies with the latest compiler 💡 Have peace of mind upgrading all your open-source libraries ☑️�Just My Code debugging Demo C++20 in action Thu, Oct 28 – 10:30am C++20’s Calendars and Time Zones in MSVC Miya Natsuhara – `Online _4 Tue, Oct 26 – 10:30am Documentation in The Era of Concepts

mode • Services are organized in hash table • IPVS DNAT • conntrack/iptables SNAT • Pros • O(1) time complexity in control/data plane • Stably runs for two decades • Support rich scheduling algorithm network is idle. • Why not use a pure eBPF service? • Not mature enough eBPF brief • Write C • Compile into eBPF assembly code • Inject to kernel • Attach to network tc hooks • Triggered by ingress/egress differ • Performance of a cluster in different time slot may differ • Due to CPU oversold • Suggestion: • Run the test against the same cluster during near time • Make CPU the bottleneck • 1 CPU handles