cleanup in CGAL/Iterator_range.h

... and add a default constructor to create an
empty range (with singular iterators).
This commit is contained in:
Laurent Rineau 2025-01-22 22:37:21 +01:00
parent 7808c6f93d
commit 9ddc5294fa
1 changed files with 37 additions and 69 deletions

View File

@ -20,54 +20,34 @@ namespace CGAL {
/*! /*!
\ingroup PkgSTLExtensionRef \ingroup PkgSTLExtensionRef
/// `CGAL::Iterator_range` is a... `CGAL::Iterator_range` encapsulates two iterators so they fulfill the `ForwardRange` concept.
The class is essentially a clone of <A
href="https://www.boost.org/doc/libs/1_55_0/libs/range/doc/html/range/reference/utilities/iterator_range.html">`boost::iterator_range`</A>,
and it additionally is derived from `std::pair`, so that one can apply `boost::tie`.
*/ */
template <typename I> template <typename I>
class Iterator_range class Iterator_range : public std::pair<I, I>
: public std::pair<I,I>{ {
typedef std::pair<I, I> Base; typedef std::pair<I, I> Base;
public: public:
typedef I iterator; typedef I iterator;
typedef I const_iterator; typedef I const_iterator;
Iterator_range() = default;
Iterator_range(I b, I e) Iterator_range(I b, I e)
: Base(b,e) : Base(b, e) {}
{}
// Iterator_range(const Iterator_range& ip)
// : Base(ip)
// {}
Iterator_range(const std::pair<I, I>& ip) Iterator_range(const std::pair<I, I>& ip)
: Base(ip) : Base(ip) {}
{}
I begin() const I begin() const { return this->first; }
{ I end() const { return this->second; }
return this->first;
}
I end() const
{
return this->second;
}
/// returns `std::distance(begin(), end())` /// returns `std::distance(begin(), end())`
std::size_t std::size_t size() const { return static_cast<std::size_t>(std::distance(begin(), end())); }
size() const
{
return static_cast<std::size_t>(std::distance(begin(), end()));
}
/// returns `std::distance(begin(), end())==0` /// returns `std::distance(begin(), end())==0`
bool empty() const bool empty() const { return begin() == end(); }
{
return begin()==end();
}
operator std::tuple<I&, I&>() operator std::tuple<I&, I&>()
{ {
@ -104,20 +84,8 @@ namespace CGAL {
} // namespace CGAL } // namespace CGAL
// At global scope... namespace boost::foreach {
template<typename T> template<typename T>
inline boost::mpl::true_ * struct is_lightweight_proxy<CGAL::Iterator_range<T>> : boost::mpl::true_ {};
boost_foreach_is_lightweight_proxy( CGAL::Iterator_range<T> *&, boost::foreach::tag )
{
return 0;
} }
namespace boost { namespace foreach
{
template<typename T>
struct is_lightweight_proxy< CGAL::Iterator_range<T> >
: mpl::true_
{
};
}}
#endif // CGAL_ITERATOR_RANGE_H #endif // CGAL_ITERATOR_RANGE_H