std::is_pointer 定义于头文件<type_traits> template<classT> structis_pointer; (C++11 起) 检查T是否为指向对象指针或指向函数指针(但不是指向成员/成员函数指针)。若T是对象/函数指针类型,则提供等于true的成员常量value。否则,value等于false。 添加is_pointer或is_pointer_v(
std::pointer_safety std::pointer_to_binary_function std::pointer_to_unary_function std::pointer_traits std::ptrdiff_t std::ptr_fun std::quick_exit std::raise std::range_error std::rank std::rbegin(std::initializer_list) std::realloc std::ref std::reference_wrapper std::reference_wrappe...
std::pointer_safety std::pointer_to_binary_function std::pointer_to_unary_function std::pointer_traits std::ptrdiff_t std::ptr_fun std::quick_exit std::raise std::range_error std::rank std::rbegin(std::initializer_list) std::realloc std::ref std::reference_wrapper std::reference_wrappe...
std::is_pointer是false为std::nullptr_t因为它不是内置的指针类型。 例 二次 代码语言:javascript 复制 #include <iostream> #include <type_traits> int main() { std::cout << std::boolalpha << std::is_null_pointer< decltype(nullptr) >::value << ' ' << std::is_null_pointer< int* >:...
代码中希望使用std::move提高效率,想探究std::move(*pointer)的用法是否合理? 分析# 这个问题不可一概而论,因为pointer所指对象的类型会影响结果。 整数# #include <iostream> int main() { int* p(new int(22));// a dumb pointer int b(std::move(*p)); std::cout<<" b = "<<b<<std::endl...
(); //bar = std::static_pointer_cast<B>(foo); std::cout << "foo's static type: " << foo->static_type << '\n'; std::cout << "foo's dynamic type: " << foo->dynamic_type << '\n'; std::cout << "bar's static type: " << bar->static_type << '\n'; std::...
T> struct std::add_pointer;如果 T 为 V& 或 V&&，则 type 为 V*…add_pointer 最后那类变成...
template<classT>structis_pointer:std::false_type{};template<classT>structis_pointer<T*>:std::true_type{};template<classT>structis_pointer<T*const>:std::true_type{};template<classT>structis_pointer<T*volatile>:std::true_type{};template<classT>structis_pointer<T*constvolatile>:std::true...
std::is_pointer_interconvertible_base_of std::is_pointer_interconvertible_with_class std::is_corresponding_member std::alignment_of std::extent std::remove_cv, std::remove_const, std::remove_volatile std::add_cv, std::add_const, std::add_volatile std::make_signed std::make_unsigned std...
his object determines the order of the elements in the container: it is a function pointer or a function object that takes two arguments of the same type as the element keys, andreturnstrueif the first argument is considered to go before the second in thestrict weak orderingit defines, and...