Item 13: Prefer const_iterators to iterators

Because in C++11 const_iterator is finally usable.

std::vector<int> values;
...
auto it = std::find(values.cbegin(), values.cend(), 1983);
values.insert(it, 1998);

Since we don’t intend to modify the element pointed by the iterator but merely want to append an element after it (hence const_iterator). This cannot be done in C++98 (you have to use plain iterator).

const_iterators are STL’s pointer-to-const.

You should call non-member version of begin/cbegin/end/cend/etc. in templates because non-member versions work with non-containers, too.

template<typename T>
void foo(T& container) {
  // Check Effective C++ Item 25 for the
  // rationale behind `using` declarations
  using std::cbegin;
  using std::cend;

  cbegin(container);
  cend(container);
}