In this example, we define a function template with multiple parameters to handle two different types in a single function. Program </> Copy #include <iostream> using namespace std; // Function template with two parameters template <typename T1, typename T2> void display(T1 a, T2 b) { co...
Explicit instantiation of a function template or of a member function of a class template cannot use inline or constexpr. If the declaration of the explicit instantiation names an implicitly-declared special member function, the program is ill-formed. ...
Consider the following program: #include <iostream> template <typename T> T addOne(T x) { return x + 1; } int main() { std::cout << addOne(1) << '\n'; std::cout << addOne(2.3) << '\n'; return 0; } Copy The compiler will effectively compile and execute this: #include...
將array傳進function,在C/C++一直是很重要的課題,在C語言中,array傳進function的是pointer,但array size一直是大問題,除了compiler不做檢查外,可能還得另外傳array size(C#則不必);C++提出reference array和function template後,有更好的方式解決這個C語言的老問題。 reference array讓compiler除了檢查array element型別...
template<typenameOutStream>classPrintIt{public:PrintIt(OutStream&os) : _os( os ){}template<typenameelemType>voidprint(constelemType&elem,chardelimiter='\n') { _os << elem << delimiter; }private:ostream&_os; };//Here is our modified program:intmain() ...
function pointer是C語言中最高級的機制,大概很多人還沒上到這裡已經學期末了,所以不少C語言工程師根本不知道C語言有function pointer;而C#的delegate大抵跟C語言的function pointer功能相同,所以很多書說delegate是物件導向的function pointer;C++的function object功能則比function pointer略強,還可配合泛型使用。
#include <iostream> template <typename T> T max(T x, T y) { return (x < y) ? y : x; } int main() { std::cout << max(2, 3.5) << '\n'; // compile error return 0; } Copy You may be surprised to find that this program won’t compile. Instead, the compiler will iss...
The output from this program is: largest of 3.11 and 3.1: 3.11 largest of 123 and 212: 212 largest of hello and hellos is: hellos But what if I want to compare numbers of different types. I can do that by rewriting the function with two template parameters. ...
// template< class R, class... Args > // class move_only_function< R( Args...) && noexcept>; // template< class R, class... Args > // class move_only_function< R( Args...) const> ; // template< class R, class... Args > ...
// in .h header file template<> extern int compare<LPCTSTR>(LPCTSTR s1, LPCTSTR s2); Of course, now you have to implement compare somewhere. Figure 7 shows part of a program I wrote to illustrate the details. I implemented the specialization in a separate module Templ.cpp that'...