Basic Concepts Definition: Variadic templates declare a template parameter pack or function parameter pack using ellipsis (…). Pack Expansion: This refers to the process of expanding the elements of a parameter pack one by one. Pack Expansion Pattern: Followed by ellipsis (…), indicating that the pattern is applied to each element in the parameter pack. … Read more
1. ConceptC++ Variadic Templates are a core feature introduced in C++11 that allows templates (class templates or function templates) to accept zero or more parameters of any type / non-type, overcoming the limitation of traditional templates that can only have a fixed number of parameters. The core concepts are “parameter packs” and “pack expansion,” enabling … Read more
In the previous section of the analysis of libc++ STL source code – type_trait, I provided a brief introduction to the type_traits of libc++’s STL library. In this section, we will explain and analyze the following five traits: add_cv_quals add_pointer add_reference aligned_storage aligned_union Before analyzing this part of the source code, we will first introduce … Read more
(Search Attributes: C++ Variadic Templates Tutorial, Template Metaprogramming in Practice, Application of Fold Expressions) Three Stages of Technical Evolution 1. C-style Approach: Flexible but Risky #include <cstdarg> double cstyle_sum(int count, …) { va_list args; va_start(args, count); // Manual maintenance of parameter count double total = 0; for(int i=0; i<count; i++) { double num = va_arg(args, … Read more
Overview This is a high-performance thread pool implemented based on the C++11 standard, featuring the following characteristics: Supports any function as a task: Can execute regular functions, member functions, lambda expressions, etc. Supports obtaining return values: Asynchronously obtain task execution results through the std::future mechanism Type-safe: Ensures type safety using C++11 template deduction Efficient synchronization: … Read more
Last year, I specifically introduced the extremely rare C++ syntax <span>……</span> in the article “What does the …… mean in C++?” which is actually an abbreviated syntax for <span>…, …</span>. The following three forms are completely equivalent: template<class… Args> void f(Args……) {} template<class… Args> void f(Args… …) {} template<class… Args> void f(Args…, …) {} The … Read more