I have a C++ class "X" which would have special meaning if a container of them were to be sent to a std::ostream.

I originally implemented it specifically for std::vector<X>:

std::ostream& operator << ( std::ostream &os, const std::vector<X> &c )
{
   // The specialized logic here expects c to be a "container" in simple
   // terms - only that c.begin() and c.end() return input iterators to X
}

If I wanted to support std::ostream << std::deque<X> or std::ostream << std::set<X> or any similar container type, the only solution I know of is to copy-paste the entire function and change only the function signature!

Is there a way to generically code operator << ( std::ostream &, const Container & )?

("Container" here would be any type that satisfies the commented description above.)