Re: Using range-based for with alternative ranges

I was thinking: How hard would it be to use the range-based for syntax
for ranges other than the full begin-end range. For instance, what if
you wanted it to traverse the container backwards instead of forwards?

What I mean is that one could write something like this:

//------------------------------------------------------------------
int table[] = { 1, 3, 5, 7, 9 };
std::vector<int> v(table, std::end(table));

std::cout << "Forwards:\n";

for(int element: table) std::cout << " " << element;
for(int element: v) std::cout << " " << element;

std::cout << "\nBackwards:\n";

for(int element: reverseRange(table)) std::cout << " " << element;
for(int element: reverseRange(v)) std::cout << " " << element;

std::cout << "\n";
//------------------------------------------------------------------

In other words, we would have a reverseRange() function that returns a
wrapper object that has reverse iterators for its begin() and end()
functions.

Other applications would be to traverse only part of the range, such as:

for(int element: subrange(table, 0, 3)) std::cout << " " << element;

I haven't found any utility wrappers for this in the new standard, so
I suppose the only way is to write such wrappers oneself.