Function Templates vs. Auto Keyword

Question

Can the auto keyword in C++11 replace function templates and specializations? If yes, what are the advantages of using template functions and specializations over simply typing a function parameter as auto?

template <typename T> void myFunction(T &arg) {     // ~ } 

vs.

void myFunction(auto &arg) {     // ~ } 

Answer 1

In a nutshell, auto cannot be used in an effort to omit the actual types of function arguments, so stick with function templates and/or overloads. auto is legally used to automatically deduce the types of variables:

auto i=5; 

Be very careful to understand the difference between the following, however:

auto x=... auto &x=... const auto &x=... auto *px=...; // vs auto px=... (They are equivalent assuming what is being                //                 assigned can be deduced to an actual pointer.) // etc... 

It is also used for suffix return types:

template <typename T, typename U> auto sum(const T &t, const U &u) -> decltype(t+u) {   return t+u; } 

Answer 2

Can the auto keyword in C++11 replace function templates and specializations?

No. There are proposals to use the keyword for this purpose, but it's not in C++11, and I think C++14 will only allow it for polymorphic lambdas, not function templates.

If yes, What are the advantages of using template functions and specializations over simply typing a function parameter as auto.

You might still want a named template parameter if you want to refer to the type; that would be more convenient than std::remove_reference<decltype(arg)>::type or whatever.