c++ - 当 C++ 中也有非模板函数时，调用专门的模板函数

Question

在这个例子中，怎么可能调用第二个函数呢？

template<class T>
T square(T a) {
    std::cout << "using generic version to square " << a << std::endl;
    return a*a;
}

/// "int" is so special -- provide a specialized function template
template<>
int square(int a) {
    std::cout << "using specialized generic version to square " << a << std::endl;
    return a*a;
}

/// and there's one more: a non-template square function for int
int square(int a) {
    std::cout << "using explicit version to square " << a << std::endl;
    return a*a;
}

提前致谢!

Answer 1

通过显式指定模板参数调用特化:

square<int>(2);

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