The iterator library that is part of the C++ Standard Library provides the following helpers for writing generic code:
#include <iterator> // helpers are defined here
template<class Container>
void foo(Container& c)
{
// Generic way to obtain (constant) iterators
auto b = std::begin(c); // (1)
auto cb = std::cbegin(c); // (2)
auto e = std::end(c); //…
Since C++11 there are elegant way to access each element of a containers (or, more generally, sequences) – so called range-for-statement. The syntaxes are follow:
template<class Container>
void foo(Container& container)
{
for (auto element : container)…
Let’s slightly modify the example from The Move Iterator Adapter in C++ post:
#include <algorithm>
#include <list>
#include <string>
#include <vector>
/// @warning BUG! PLEASE, DON'T USE!
auto deep_copy_to_list(const…
The dereference prefix operator * being applied to iterator returns the lvalue reference to the element pointed by the iterator. Therefore, algorithms such as std::copy or std::transform calls copying constructors of processed elements, for example:
#include <algorithm>
#include <list>
#include <string>
#include <vector>
auto deep_copy_to_list(const…
By using bidirectional iterator or random access iterator (see Iterator Categories in C++) it’s possible to traverse the sequence in backward direction by using operator -- or by using the special adapter template class std::reverse_iterator. But why to bother with…
Iterator abstracts the concept of pointer to the sequence in range [begin, end), and thus provides the following basic operations:
dereference to obtain the current element;movement to point the next element;comparison to determine at least the end of…
