Compile time if-else statement

Following Modern C++.

#include

using namespace std;

template
struct int2type
{
enum { value = v };
};

template
class Factory
{
private:
T* create(int2type)
{
cout << "new T" << endl; return new T; } T* create(int2type)
{
cout << "new T(\"hi\")" << endl; return new T("hi"); } public: T* create() { return create(int2type()); }
};

int main()
{
Factory f;
Factory f2;

string* s = f.create();
cout << *s << endl; delete s; s = f2.create(); cout << *s << endl; delete s; return EXIT_SUCCESS; } [/code] [output] C:\> a.exe
new T

new T(“hi”)
hi
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int2type class was used to convert the given parameter into type parameter. According to the type of int2type, proper method for creating T is called.