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@preshing
Created January 3, 2018 21:54
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Use SFINAE to call member function if present
#include <iostream>
class Foo {
public:
void bar() {
std::cout << "Foo::bar() called" << std::endl;
}
};
class Foo2 {
};
// callBarIfPresent(T*)
// This version will be called if T::bar() exists:
template <class T> auto callBarIfPresent(T* obj) -> decltype(obj->bar()) {
return obj->bar();
}
// This version will be called otherwise:
inline void callBarIfPresent(...) {
std::cout << "No member function called" << std::endl;
}
int main()
{
Foo foo;
callBarIfPresent(&foo);
Foo2 foo2;
callBarIfPresent(&foo2);
return 0;
}
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