First part of P0202: Adding constexpr modifiers to functions in <algorithm> and <utility>. This commit is all the is_XXX algorithms.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@322489 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/algorithm b/include/algorithm
index c527860..cea6b24 100644
--- a/include/algorithm
+++ b/include/algorithm
@@ -39,11 +39,11 @@
InputIterator for_each_n(InputIterator first, Size n, Function f); // C++17
template <class InputIterator, class T>
- InputIterator
+ constexpr InputIterator // constexpr in C++20
find(InputIterator first, InputIterator last, const T& value);
template <class InputIterator, class Predicate>
- InputIterator
+ constexpr InputIterator // constexpr in C++20
find_if(InputIterator first, InputIterator last, Predicate pred);
template<class InputIterator, class Predicate>
@@ -127,22 +127,22 @@
BinaryPredicate pred); // **C++14**
template<class ForwardIterator1, class ForwardIterator2>
- bool
+ constexpr bool // constexpr in C++20
is_permutation(ForwardIterator1 first1, ForwardIterator1 last1,
ForwardIterator2 first2);
template<class ForwardIterator1, class ForwardIterator2>
- bool
+ constexpr bool // constexpr in C++20
is_permutation(ForwardIterator1 first1, ForwardIterator1 last1,
ForwardIterator2 first2, ForwardIterator2 last2); // **C++14**
template<class ForwardIterator1, class ForwardIterator2, class BinaryPredicate>
- bool
+ constexpr bool // constexpr in C++20
is_permutation(ForwardIterator1 first1, ForwardIterator1 last1,
ForwardIterator2 first2, BinaryPredicate pred);
template<class ForwardIterator1, class ForwardIterator2, class BinaryPredicate>
- bool
+ constexpr bool // constexpr in C++20
is_permutation(ForwardIterator1 first1, ForwardIterator1 last1,
ForwardIterator2 first2, ForwardIterator2 last2,
BinaryPredicate pred); // **C++14**
@@ -302,7 +302,7 @@
UniformRandomNumberGenerator&& g);
template <class InputIterator, class Predicate>
- bool
+ constexpr bool // constexpr in C++20
is_partitioned(InputIterator first, InputIterator last, Predicate pred);
template <class ForwardIterator, class Predicate>
@@ -325,7 +325,7 @@
partition_point(ForwardIterator first, ForwardIterator last, Predicate pred);
template <class ForwardIterator>
- bool
+ constexpr bool // constexpr in C++20
is_sorted(ForwardIterator first, ForwardIterator last);
template <class ForwardIterator, class Compare>
@@ -513,19 +513,19 @@
sort_heap(RandomAccessIterator first, RandomAccessIterator last, Compare comp);
template <class RandomAccessIterator>
- bool
+ constexpr bool // constexpr in C++20
is_heap(RandomAccessIterator first, RandomAccessiterator last);
template <class RandomAccessIterator, class Compare>
- bool
+ constexpr bool // constexpr in C++20
is_heap(RandomAccessIterator first, RandomAccessiterator last, Compare comp);
template <class RandomAccessIterator>
- RandomAccessIterator
+ constexpr RandomAccessIterator // constexpr in C++20
is_heap_until(RandomAccessIterator first, RandomAccessiterator last);
template <class RandomAccessIterator, class Compare>
- RandomAccessIterator
+ constexpr RandomAccessIterator // constexpr in C++20
is_heap_until(RandomAccessIterator first, RandomAccessiterator last, Compare comp);
template <class ForwardIterator>
@@ -990,7 +990,7 @@
// find
template <class _InputIterator, class _Tp>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
_InputIterator
find(_InputIterator __first, _InputIterator __last, const _Tp& __value_)
{
@@ -1003,7 +1003,7 @@
// find_if
template <class _InputIterator, class _Predicate>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
_InputIterator
find_if(_InputIterator __first, _InputIterator __last, _Predicate __pred)
{
@@ -1395,17 +1395,18 @@
// is_permutation
template<class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate>
-bool
+_LIBCPP_CONSTEXPR_AFTER_CXX17 bool
is_permutation(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
_ForwardIterator2 __first2, _BinaryPredicate __pred)
{
- // shorten sequences as much as possible by lopping of any equal parts
+// shorten sequences as much as possible by lopping of any equal prefix
for (; __first1 != __last1; ++__first1, (void) ++__first2)
if (!__pred(*__first1, *__first2))
- goto __not_done;
- return true;
-__not_done:
- // __first1 != __last1 && *__first1 != *__first2
+ break;
+ if (__first1 == __last1)
+ return true;
+
+// __first1 != __last1 && *__first1 != *__first2
typedef typename iterator_traits<_ForwardIterator1>::difference_type _D1;
_D1 __l1 = _VSTD::distance(__first1, __last1);
if (__l1 == _D1(1))
@@ -1415,11 +1416,8 @@
// equal elements in [f2, l2)
for (_ForwardIterator1 __i = __first1; __i != __last1; ++__i)
{
- // Have we already counted the number of *__i in [f1, l1)?
- for (_ForwardIterator1 __j = __first1; __j != __i; ++__j)
- if (__pred(*__j, *__i))
- goto __next_iter;
- {
+ // Have we already counted the number of *__i in [f1, l1)?
+ if (find(__first1, __i, *__i) == __i) {
// Count number of *__i in [f2, l2)
_D1 __c2 = 0;
for (_ForwardIterator2 __j = __first2; __j != __last2; ++__j)
@@ -1435,13 +1433,12 @@
if (__c1 != __c2)
return false;
}
-__next_iter:;
}
return true;
}
template<class _ForwardIterator1, class _ForwardIterator2>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
bool
is_permutation(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
_ForwardIterator2 __first2)
@@ -1453,19 +1450,21 @@
#if _LIBCPP_STD_VER > 11
template<class _BinaryPredicate, class _ForwardIterator1, class _ForwardIterator2>
-bool
+_LIBCPP_CONSTEXPR_AFTER_CXX17 bool
__is_permutation(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
_ForwardIterator2 __first2, _ForwardIterator2 __last2,
_BinaryPredicate __pred,
forward_iterator_tag, forward_iterator_tag )
{
- // shorten sequences as much as possible by lopping of any equal parts
+// shorten sequences as much as possible by lopping of any equal prefix
for (; __first1 != __last1 && __first2 != __last2; ++__first1, (void) ++__first2)
if (!__pred(*__first1, *__first2))
- goto __not_done;
- return __first1 == __last1 && __first2 == __last2;
-__not_done:
- // __first1 != __last1 && __first2 != __last2 && *__first1 != *__first2
+ break;
+ if (__first1 == __last1)
+ return __first2 == __last2;
+ else if (__first2 == __last2)
+ return false;
+
typedef typename iterator_traits<_ForwardIterator1>::difference_type _D1;
_D1 __l1 = _VSTD::distance(__first1, __last1);
@@ -1478,11 +1477,8 @@
// equal elements in [f2, l2)
for (_ForwardIterator1 __i = __first1; __i != __last1; ++__i)
{
- // Have we already counted the number of *__i in [f1, l1)?
- for (_ForwardIterator1 __j = __first1; __j != __i; ++__j)
- if (__pred(*__j, *__i))
- goto __next_iter;
- {
+ // Have we already counted the number of *__i in [f1, l1)?
+ if (find(__first1, __i, *__i) == __i) {
// Count number of *__i in [f2, l2)
_D1 __c2 = 0;
for (_ForwardIterator2 __j = __first2; __j != __last2; ++__j)
@@ -1498,13 +1494,12 @@
if (__c1 != __c2)
return false;
}
-__next_iter:;
}
return true;
}
template<class _BinaryPredicate, class _RandomAccessIterator1, class _RandomAccessIterator2>
-bool
+_LIBCPP_CONSTEXPR_AFTER_CXX17 bool
__is_permutation(_RandomAccessIterator1 __first1, _RandomAccessIterator2 __last1,
_RandomAccessIterator1 __first2, _RandomAccessIterator2 __last2,
_BinaryPredicate __pred,
@@ -1518,7 +1513,7 @@
}
template<class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
bool
is_permutation(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
_ForwardIterator2 __first2, _ForwardIterator2 __last2,
@@ -1531,7 +1526,7 @@
}
template<class _ForwardIterator1, class _ForwardIterator2>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
bool
is_permutation(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
_ForwardIterator2 __first2, _ForwardIterator2 __last2)
@@ -3231,7 +3226,7 @@
}
template <class _InputIterator, class _Predicate>
-bool
+_LIBCPP_CONSTEXPR_AFTER_CXX17 bool
is_partitioned(_InputIterator __first, _InputIterator __last, _Predicate __pred)
{
for (; __first != __last; ++__first)
@@ -3639,7 +3634,7 @@
// is_sorted_until
template <class _ForwardIterator, class _Compare>
-_ForwardIterator
+_LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator
is_sorted_until(_ForwardIterator __first, _ForwardIterator __last, _Compare __comp)
{
if (__first != __last)
@@ -3656,7 +3651,7 @@
}
template<class _ForwardIterator>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
_ForwardIterator
is_sorted_until(_ForwardIterator __first, _ForwardIterator __last)
{
@@ -3666,7 +3661,7 @@
// is_sorted
template <class _ForwardIterator, class _Compare>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
bool
is_sorted(_ForwardIterator __first, _ForwardIterator __last, _Compare __comp)
{
@@ -3674,7 +3669,7 @@
}
template<class _ForwardIterator>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
bool
is_sorted(_ForwardIterator __first, _ForwardIterator __last)
{
@@ -4834,7 +4829,7 @@
// is_heap_until
template <class _RandomAccessIterator, class _Compare>
-_RandomAccessIterator
+_LIBCPP_CONSTEXPR_AFTER_CXX17 _RandomAccessIterator
is_heap_until(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
{
typedef typename _VSTD::iterator_traits<_RandomAccessIterator>::difference_type difference_type;
@@ -4861,7 +4856,7 @@
}
template<class _RandomAccessIterator>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
_RandomAccessIterator
is_heap_until(_RandomAccessIterator __first, _RandomAccessIterator __last)
{
@@ -4871,7 +4866,7 @@
// is_heap
template <class _RandomAccessIterator, class _Compare>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
bool
is_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
{
@@ -4879,7 +4874,7 @@
}
template<class _RandomAccessIterator>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
bool
is_heap(_RandomAccessIterator __first, _RandomAccessIterator __last)
{