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authormikhnenko <[email protected]>2023-09-20 11:01:13 +0300
committermikhnenko <[email protected]>2023-09-20 11:29:08 +0300
commitf5b051f5e09f00265229985ba5fd47aa5c8959ff (patch)
tree7e11605ad566f09451623a1ac34cc644bae804ab /contrib/libs/cxxsupp/libcxxmsvc/include/__algorithm/shift_left.h
parent8ed995cdfb22a3dfa790b0a6ae7750d9dc85db7b (diff)
Split libcxx on msvc/other
Diffstat (limited to 'contrib/libs/cxxsupp/libcxxmsvc/include/__algorithm/shift_left.h')
-rw-r--r--contrib/libs/cxxsupp/libcxxmsvc/include/__algorithm/shift_left.h56
1 files changed, 56 insertions, 0 deletions
diff --git a/contrib/libs/cxxsupp/libcxxmsvc/include/__algorithm/shift_left.h b/contrib/libs/cxxsupp/libcxxmsvc/include/__algorithm/shift_left.h
new file mode 100644
index 00000000000..33f06d57e23
--- /dev/null
+++ b/contrib/libs/cxxsupp/libcxxmsvc/include/__algorithm/shift_left.h
@@ -0,0 +1,56 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_SHIFT_LEFT_H
+#define _LIBCPP___ALGORITHM_SHIFT_LEFT_H
+
+#include <__algorithm/move.h>
+#include <__config>
+#include <__iterator/iterator_traits.h>
+#include <type_traits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER > 17
+
+template <class _ForwardIterator>
+inline _LIBCPP_INLINE_VISIBILITY constexpr
+_ForwardIterator
+shift_left(_ForwardIterator __first, _ForwardIterator __last,
+ typename iterator_traits<_ForwardIterator>::difference_type __n)
+{
+ if (__n == 0) {
+ return __last;
+ }
+
+ _ForwardIterator __m = __first;
+ if constexpr (__is_cpp17_random_access_iterator<_ForwardIterator>::value) {
+ if (__n >= __last - __first) {
+ return __first;
+ }
+ __m += __n;
+ } else {
+ for (; __n > 0; --__n) {
+ if (__m == __last) {
+ return __first;
+ }
+ ++__m;
+ }
+ }
+ return _VSTD::move(__m, __last, __first);
+}
+
+#endif // _LIBCPP_STD_VER > 17
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ALGORITHM_SHIFT_LEFT_H