https://quhongbin.github.io/categories/%E7%BC%96%E7%A8%8B%E8%AF%AD%E8%A8%80/Recent content in 编程语言 on 我的博客Hugozh-CNMon, 31 Aug 2026 00:00:00 +0800https://quhongbin.github.io/notes/constexpr-eval-order/Mon, 31 Aug 2026 00:00:00 +0800https://quhongbin.github.io/notes/constexpr-eval-order/<p><code>constexpr</code> 函数<strong>不保证</strong>在编译期求值。只有在需要常量表达式的场合——数组长度、模板实参、<code>static_assert</code>——编译器才强制走编译期；其它情况下它可以退化成普通的函数调用。</p>https://quhongbin.github.io/posts/1/01/c-templates/Mon, 01 Jan 0001 00:00:00 +0000https://quhongbin.github.io/posts/1/01/c-templates/<h1 id="c-templates">C++ Templates</h1> <p>Templates are C++'s mechanism for <strong>generic programming</strong> &mdash; writing code that works with any type without repeating yourself. Unlike runtime polymorphism (virtual functions), templates are resolved entirely at compile time: the compiler generates a separate copy of the function or class for each set of type arguments actually used. This is called <strong>template instantiation</strong>.</p> <p>Templates are the foundation of the C++ Standard Library: <code>std::vector&lt;int&gt;</code>, <code>std::map&lt;std::string, double&gt;</code>, <code>std::sort(begin, end)</code> &mdash; all templates. They power everything from containers to algorithms to smart pointers. Understanding templates deeply means understanding how modern C++ achieves its combination of abstraction and zero-overhead performance.</p>