Make next/prev/advance/distance operations on iterators be constexpr. I missed this when I implemented the rest of P0031R0
llvm-svn: 303281
Cr-Mirrored-From: sso://chromium.googlesource.com/_direct/external/github.com/llvm/llvm-project
Cr-Mirrored-Commit: f51ee632475654a396f93da9d36841989e1c7742
diff --git a/include/iterator b/include/iterator
index 47a7811..4aa4474 100644
--- a/include/iterator
+++ b/include/iterator
@@ -64,14 +64,23 @@
struct bidirectional_iterator_tag : public forward_iterator_tag {};
struct random_access_iterator_tag : public bidirectional_iterator_tag {};
+// 27.4.3, iterator operations
// extension: second argument not conforming to C++03
-template <class InputIterator>
-void advance(InputIterator& i,
+template <class InputIterator> // constexpr in C++17
+ constexpr void advance(InputIterator& i,
typename iterator_traits<InputIterator>::difference_type n);
-template <class InputIterator>
-typename iterator_traits<InputIterator>::difference_type
-distance(InputIterator first, InputIterator last);
+template <class InputIterator> // constexpr in C++17
+ constexpr typename iterator_traits<InputIterator>::difference_type
+ distance(InputIterator first, InputIterator last);
+
+template <class InputIterator> // constexpr in C++17
+ constexpr InputIterator next(InputIterator x,
+typename iterator_traits<InputIterator>::difference_type n = 1);
+
+template <class BidirectionalIterator> // constexpr in C++17
+ constexpr BidirectionalIterator prev(BidirectionalIterator x,
+ typename iterator_traits<BidirectionalIterator>::difference_type n = 1);
template <class Iterator>
class reverse_iterator
@@ -529,7 +538,7 @@
};
template <class _InputIter>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
void __advance(_InputIter& __i,
typename iterator_traits<_InputIter>::difference_type __n, input_iterator_tag)
{
@@ -538,7 +547,7 @@
}
template <class _BiDirIter>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
void __advance(_BiDirIter& __i,
typename iterator_traits<_BiDirIter>::difference_type __n, bidirectional_iterator_tag)
{
@@ -551,7 +560,7 @@
}
template <class _RandIter>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
void __advance(_RandIter& __i,
typename iterator_traits<_RandIter>::difference_type __n, random_access_iterator_tag)
{
@@ -559,7 +568,7 @@
}
template <class _InputIter>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
void advance(_InputIter& __i,
typename iterator_traits<_InputIter>::difference_type __n)
{
@@ -567,7 +576,7 @@
}
template <class _InputIter>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
typename iterator_traits<_InputIter>::difference_type
__distance(_InputIter __first, _InputIter __last, input_iterator_tag)
{
@@ -578,7 +587,7 @@
}
template <class _RandIter>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
typename iterator_traits<_RandIter>::difference_type
__distance(_RandIter __first, _RandIter __last, random_access_iterator_tag)
{
@@ -586,7 +595,7 @@
}
template <class _InputIter>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
typename iterator_traits<_InputIter>::difference_type
distance(_InputIter __first, _InputIter __last)
{
@@ -594,7 +603,7 @@
}
template <class _InputIter>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
_InputIter
next(_InputIter __x,
typename iterator_traits<_InputIter>::difference_type __n = 1,
@@ -605,7 +614,7 @@
}
template <class _BidiretionalIter>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
_BidiretionalIter
prev(_BidiretionalIter __x,
typename iterator_traits<_BidiretionalIter>::difference_type __n = 1,