Class CartesianProductIterator

template<typename T>
class CartesianProductIterator : public boost::iterator_facade<CartesianProductIterator<T>, std::vector<T::value_type::value_type> const, boost::forward_traversal_tag>

Class iterating over the Cartesian product of a forward iterable container of forward iterable containers

Unnamed Group

template<>
using OuterContainer = T

Give types more descriptive names.

template<>
using Container = typename T::value_type

template<>
using Content = typename T::value_type::value_type

Public Functions

CartesianProductIterator()

Delete default constructor.

CartesianProductIterator(T const &structure, std::size_t pos)

Constructor setting the underlying iterator and position.

Parameters

• [in] structure: The underlying structure

• [in] pos: The position the iterator should be initialized to. std::numeric_limits<std::size_t>::max()stands for the end, the position after the last element.

Private Functions

void increment()

Increment iterator.

bool equal(CartesianProductIterator<T> const &other) const

Check for equality.

std::vector<typename T::value_type::value_type> const &dereference() const

Dereference iterator.

Private Members

OuterContainer const &structure_

The part we are iterating over.

std::vector<typename Container::const_iterator> position_

The position in the Cartesian product.

For each element of structure_, give the position in it. The empty vector represents the end position. Note that this vector has a size equal to structure->size(), or is empty.

std::size_t absolutePosition_ = 0

The position just indexed by an integer.

std::vector<typename Container::const_iterator> cbegins_

The begin iterators, saved for convenience and performance.

std::vector<typename Container::const_iterator> cends_

The end iterators, saved for convenience and performance.

std::vector<std::vector<Content>> result_ = {std::vector<Content>()}

Used for returning references.

We initialize with one empty element, so that we only need to add more elements in increment().

std::size_t size_ = 0

The size of the instance of OuterContainer.

Friends

friend CartesianProductIterator::boost::iterator_core_access

Grant access to boost::iterator_facade.