dash/src/reverse_iterator.h
Wladimir J. van der Laan fdf3f25a0a
Merge #10969: Declare single-argument (non-converting) constructors "explicit"
64fb0ac Declare single-argument (non-converting) constructors "explicit" (practicalswift)

Pull request description:

  Declare single-argument (non-converting) constructors `explicit`.

  In order to avoid unintended implicit conversions.

  For a more thorough discussion, see ["C.46: By default, declare single-argument constructors explicit"](http://isocpp.github.io/CppCoreGuidelines/CppCoreGuidelines#c46-by-default-declare-single-argument-constructors-explicit) in the C++ Core Guidelines (Stroustrup & Sutter).

Tree-SHA512: e0c6922e56b11fa402621a38656d8b1122d16dd8f160e78626385373cf184ac7f26cb4c1851eca47e9b0dbd5e924e39a85c3cbdcb627a05ee3a655ecf5f7a0f1
2020-01-10 10:33:57 -06:00

40 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