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#include <iostream>
struct GetValueImpl
{
    template <typename T>
    static auto test(int) -> decltype(
        std::declval<T&>().GetValue(0),
        std::true_type{});
    template <typename...>
    static std::false_type test(...);
};
template <typename T>
struct GetValueDefined : public decltype(GetValueImpl::test<T>(0)) {};
 
template <typename Derived, int X>
class Base
{
    public:
 
    // I want to define this function only if GetValue is defined in Derived
    template <typename... Args>
    auto Test(const Args&...) -> typename std::enable_if<GetValueDefined<Derived>::value>::type
    {
    }
};
 
template <std::int32_t val>
class DerivedExample : public Base<DerivedExample<val>, 1>
{
    public:
    template <typename T>
    int GetValue() {return 0;}
};
 
int main() {
    DerivedExample<1> d;
    d.Test(1, 2);
    return 0;
}
 

prog.cpp: In instantiation of ‘class Base<DerivedExample<1>, 1>’:
prog.cpp:27:7:   required from ‘class DerivedExample<1>’
prog.cpp:35:23:   required from here
prog.cpp:21:10: error: no type named ‘type’ in ‘struct std::enable_if<false, void>’
     auto Test(const Args&...) -> typename std::enable_if<GetValueDefined<Derived>::value>::type
          ^
prog.cpp: In function ‘int main()’:
prog.cpp:36:7: error: ‘class DerivedExample<1>’ has no member named ‘Test’
     d.Test(1, 2);
       ^

Standard output is empty