std::vector<int> v(1'000'000); std::for_each(std::execution::par, v.begin(), v.end(), [](int& x) x *= 2; ); Portable filesystem operations: paths, directories, permissions, etc.
if (auto it = m.find(key); it != m.end()) // use it here // it goes out of scope Permits defining variables in header files without violating the One Definition Rule (ODR). Essential for header-only libraries. c++ 2017
template<typename... Args> auto sum(Args... args) return (args + ...); // right fold [](int& x) x *= 2
Allows declaring a variable scoped to the statement. Portable filesystem operations: paths
std::map<int, std::string> src1,"a"; std::map<int, std::string> dst; dst.insert(src.extract(1)); Distinct enum class for raw memory representation (no arithmetic).
Compile-time conditional compilation inside templates, discarding non-taken branches entirely.
namespace fs = std::filesystem; for (auto& p : fs::directory_iterator(".")) std::cout << p.path() << '\n';