C++ how to call templated constructor

Question

How can I change the code below to allow creation of a Base object with a templated constructor?

struct Base {
template <typename T>
Base(int a) {}
};

 int main(int argc, char const *argv[])
{
    Base *b = new Base<char>(2);
    delete b;
    return 0;
}

score -3 · Answer 1 · edited May 23 '17 at 12:01

-3

This thread seems to answer your question:

C++ template constructor

The bottom line is that it doesn't seem to be supported; and it's unclear what it would achieve.

edited May 23 '17 at 12:01

Community

1
1

answered Apr 26 '13 at 18:27

Topological Sort

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Sometimes constructors handle many types but the data is only used temporarily, so having the class itself be templated is reduntant. There's not a huge need for it I guess but it makes sense. – iPherian Nov 03 '16 at 22:42

score -4 · Answer 2 · answered Apr 26 '13 at 18:29

The question is a bit vague. Is your intent to replace the "int a" in the Base ctor with "T a"? If so, you might want to use function template type inference, like this:

template<typename T>
Base<T> CreateBase(T a)
{
  return new Base<T>(a);
}

// Call site avoids template clutter
auto base = CreateBase(2);

C++ how to call templated constructor

2 Answers2