Clean ways to write multiple 'for' loops

Question

For an array with multiple dimensions, we usually need to write a for loop for each of its dimensions. For example:

vector< vector< vector         


        

Answer 1

One idea is to write an iterable pseudo-container class that "contains" the set of all multi-index tuples you'll index over. No implementation here because it'll take too long but the idea is that you should be able to write...

multi_index mi (10, 8, 5);
  //  The pseudo-container whose iterators give {0,0,0}, {0,0,1}, ...

for (auto i : mi)
{
  //  In here, use i[0], i[1] and i[2] to access the three index values.
}