lbrycrd/src/reverse_iterator.h
practicalswift 64fb0ac016 Declare single-argument (non-converting) constructors "explicit"
In order to avoid unintended implicit conversions.
2017-08-16 16:33:25 +02:00

39 lines
776 B
C++

// Taken from https://gist.github.com/arvidsson/7231973
#ifndef BITCOIN_REVERSE_ITERATOR_H
#define BITCOIN_REVERSE_ITERATOR_H
/**
* Template used for reverse iteration in C++11 range-based for loops.
*
* std::vector<int> v = {1, 2, 3, 4, 5};
* for (auto x : reverse_iterate(v))
* std::cout << x << " ";
*/
template <typename T>
class reverse_range
{
T &m_x;
public:
explicit reverse_range(T &x) : m_x(x) {}
auto begin() const -> decltype(this->m_x.rbegin())
{
return m_x.rbegin();
}
auto end() const -> decltype(this->m_x.rend())
{
return m_x.rend();
}
};
template <typename T>
reverse_range<T> reverse_iterate(T &x)
{
return reverse_range<T>(x);
}
#endif // BITCOIN_REVERSE_ITERATOR_H