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#pragma once
#include <util/system/yassert.h>
#include <iterator>
#include <utility>
template <typename TBegin, typename TEnd = TBegin>
struct TIteratorRange {
using TElement = std::remove_reference_t<decltype(*std::declval<TBegin>())>;
TIteratorRange(TBegin begin, TEnd end)
: Begin_(begin)
, End_(end)
{
}
TIteratorRange()
: TIteratorRange(TBegin{}, TEnd{})
{
}
TBegin begin() const {
return Begin_;
}
TEnd end() const {
return End_;
}
bool empty() const {
// because range based for requires exactly '!='
return !(Begin_ != End_);
}
private:
TBegin Begin_;
TEnd End_;
};
template <class TIterator>
class TIteratorRange<TIterator, TIterator> {
public:
using iterator = TIterator;
using const_iterator = TIterator;
using value_type = typename std::iterator_traits<iterator>::value_type;
using reference = typename std::iterator_traits<iterator>::reference;
using const_reference = typename std::iterator_traits<const_iterator>::reference;
using difference_type = typename std::iterator_traits<iterator>::difference_type;
using size_type = std::size_t;
TIteratorRange()
: Begin_()
, End_()
{
}
TIteratorRange(TIterator begin, TIterator end)
: Begin_(begin)
, End_(end)
{
}
TIterator begin() const {
return Begin_;
}
TIterator end() const {
return End_;
}
Y_PURE_FUNCTION bool empty() const {
return Begin_ == End_;
}
size_type size() const {
return End_ - Begin_;
}
reference operator[](size_t at) const {
Y_ASSERT(at < size());
return *(Begin_ + at);
}
private:
TIterator Begin_;
TIterator End_;
};
template <class TIterator>
TIteratorRange<TIterator> MakeIteratorRange(TIterator begin, TIterator end) {
return TIteratorRange<TIterator>(begin, end);
}
template <class TIterator>
TIteratorRange<TIterator> MakeIteratorRange(const std::pair<TIterator, TIterator>& range) {
return TIteratorRange<TIterator>(range.first, range.second);
}
template <class TBegin, class TEnd>
TIteratorRange<TBegin, TEnd> MakeIteratorRange(TBegin begin, TEnd end) {
return {begin, end};
}
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