Thestd::piecewise_constructmarker works well in conjunction withstd::forward_as_tuple: template<typename...Args> auto make_t1_with_default_t2(Args&&...args) { return std::pair<T1, T2>( std::piecewise_construct, std::forward_as_tuple(std::forward<Args>(args)...), std::make_tuple())...
最后，forward_as_tuple生成一个引用元组，但是引用的东西仍然必须存储在 * 某个地方 *。
最后，forward_as_tuple生成一个引用元组，但是引用的东西仍然必须存储在 * 某个地方 *。
如果你想以元组的形式储存东西，你可以。只需在lambda中捕获元组，然后使用std::get在lambda的主体中访问...
参阅make_tuple 创建一个 tuple 对象,其类型根据各实参类型定义 (函数模板) tie 创建左值引用的 tuple,或将 tuple 解包为独立对象 (函数模板) tuple_cat 通过连接任意数量的元组来创建一个tuple (函数模板) apply (C++17) 以一个实参的元组来调用函数 (函数模板) ...
make_tuple (C++11) creates atupleobject of the type defined by the argument types (function template) tie (C++11) creates atupleof lvalue references or unpacks a tuple into individual objects (function template) tuple_cat (C++11) creates atupleby concatenating any number of tuples ...
C++ Tuple::forward_as_tuple() Function - The C++ std::tuple::forward_as_tuple() function is used to construct a tuple by fowarding its arguments, preserving their original types and forwarding them as rvalue references. unlike the std::make_tuple() funct