C++2019 Site

auto result = std::vector1,2,3,4,5 | rv::filter([](int x) return x%2==0; ) | rv::transform([](int x) return x*x; ); // result = 4, 16

C++17 made everyday C++ cleaner, safer, and more expressive. C++20 is comparable to C++11 in scope. It introduced four major language features and a host of library enhancements. 1. Concepts – Constraints for Templates template<typename T> concept Numeric = std::is_arithmetic_v<T>; template<Numeric T> T add(T a, T b) return a + b; c++2019

No more messy iterator pairs; lazy evaluation and chaining. generator<int> fibonacci() int a = 0, b = 1; while (true) co_yield a; // suspend and return a auto next = a + b; a = b; b = next; Embrace it

// Error: add("a", "b") – string not numeric checkable template requirements. #include &lt

If you’re still writing new / delete or raw loops with index variables, . Embrace it. “C++20 feels like a new language – but still C++.” – Bjarne Stroustrup

Concepts replace SFINAE with readable, checkable template requirements. #include <ranges> #include <vector> namespace rv = std::ranges::views;

int main() for (const auto& entry : fs::directory_iterator(".")) auto [path, status] = std::pairentry.path(), entry.status(); if (fs::is_regular_file(status)) std::cout << "File: " << path.filename() << '\n';