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When a template publicly inherits from another template, aren't the base public methods supposed to be accessible?
template <int a> class Test { public: Test() {} int MyMethod1() { return a; } }; template <int b> class Another : public Test<b> { public: Another() {} void MyMethod2() { MyMethod1(); } }; int main() { Another<5> a; a.MyMethod1(); a.MyMethod2(); } Well, GCC craps out on this... I must be missing something totally obvious (brain melt). Help?
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Class Template Inheritance in C++Inheriting from a template class is feasible. All regular inheritance and polymorphism rules apply. If we need the new derived class to be general, we must make it a template class with a template argument sent to the base class.
Templates provide sortability in a much nicer way, since the sortee doesn't need to know that it's being sorted. Complex inheritance typically results when you work with a forced mindset that everything must be an inheritance hierarchy, which is in fact rarely appropriate.
Deriving from a non-template base classIt is quite possible to have a template class inherit from a 'normal' class. This mechanism is recommended if your template class has a lot of non-template attributes and operations. Instead of putting them in the template class, put them into a non-template base class.
This is part of the rules concerning dependent names. Method1 is not a dependent name in the scope of Method2. So the compiler doesn't look it up in dependent base classes.
There two ways to fix that: Using this or specifying the base type. More details on this very recent post or at the C++ FAQ. Also notice that you missed the public keyword and a semi-colon. Here's a fixed version of your code.
template <int a> class Test { public: Test() {} int MyMethod1() { return a; } }; template <int b> class Another : public Test<b> { public: Another() {} void MyMethod2() { Test<b>::MyMethod1(); } }; int main() { Another<5> a; a.MyMethod1(); a.MyMethod2(); } If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
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