Question

I’ve a function taking a constant iterator in parameter and I would like to make a recursive call on the function, but incrementing my iterator by one (without modifying the iterator itself).

The only solution I found was to create a copy of the iterator, and pre-increment this copy to finally pass it as parameter of my function call.

func(const FowardIterator & i, const container & c) {
  // lot of very smart code

  FowardIterator next = i;

  ++next;
  func(next, c);
}

Is there any simpler way to do this, one which does not involve creating a temporary iterator ?

Answer 1

An iterator should be extremely fast to copy, so there’s really no reason to accept one by const&; pass-by-value should be fine, and would allow you to avoid copying the iterator explicitly in the body of the function.

That said, you can also use std::next to copy an iterator and advance it all in one step:

func(std::next(i), c);