Question

Suppose I have a function template:

template <typename T>
std::string foo(const T& x)
{
    return some_computation_involving(x);
}

If x is already a string, I just want to pass it back verbatim. Should I specialize the function template?

template <>
std::string foo(const std::string& x)
{
    return x;
}

Or should I provide a non-template function?

std::string foo(const std::string& x)
{
    return x;
}

Under what circumstances should I choose which option, and what are the pitfalls I need to be aware of?

Answer 1

Prefer overload over function specialization, says Herb Sutter. He explains this in his articles:

• Why Not Specialize Function Templates?
• Template Specialization and Overloading