#define LLVM_ADT_ITERATOR_RANGE_H
#include <utility>
+#include <iterator>
namespace llvm {
-template <typename Range>
-struct range_traits {
- typedef typename Range::difference_type difference_type;
-};
-
/// \brief A range adaptor for a pair of iterators.
///
/// This just wraps two iterators into a range-compatible interface. Nothing
IteratorT begin_iterator, end_iterator;
public:
- // FIXME: We should be using iterator_traits to determine the
- // difference_type, but most of our iterators do not expose anything like it.
- typedef int difference_type;
-
- iterator_range() {}
+ //TODO: Add SFINAE to test that the Container's iterators match the range's
+ // iterators.
+ template <typename Container>
+ iterator_range(Container &&c)
+ //TODO: Consider ADL/non-member begin/end calls.
+ : begin_iterator(c.begin()), end_iterator(c.end()) {}
iterator_range(IteratorT begin_iterator, IteratorT end_iterator)
: begin_iterator(std::move(begin_iterator)),
end_iterator(std::move(end_iterator)) {}
IteratorT end() const { return end_iterator; }
};
-/// \brief Determine the distance between the end() and begin() iterators of
-/// a range. Analogous to std::distance().
-template <class Range>\r
-typename range_traits<Range>::difference_type distance(Range R) {\r
- return std::distance(R.begin(), R.end());\r
+/// \brief Convenience function for iterating over sub-ranges.
+///
+/// This provides a bit of syntactic sugar to make using sub-ranges
+/// in for loops a bit easier. Analogous to std::make_pair().
+template <class T> iterator_range<T> make_range(T x, T y) {
+ return iterator_range<T>(std::move(x), std::move(y));
+}
+
+template <typename T> iterator_range<T> make_range(std::pair<T, T> p) {
+ return iterator_range<T>(std::move(p.first), std::move(p.second));
}
-/// \brief Copies members of a range into the output iterator provided.
-/// Analogous to std::copy.
-template <class Range, class OutputIterator>
-OutputIterator copy(Range In, OutputIterator Result) {
- return std::copy(In.begin(), In.end(), Result);
+template<typename T>
+iterator_range<decltype(begin(std::declval<T>()))> drop_begin(T &&t, int n) {
+ return make_range(std::next(begin(t), n), end(t));
}
}