1 files changed, 97 insertions, 0 deletions
diff --git a/boost/algorithm/find_backward.hpp b/boost/algorithm/find_backward.hpp
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+++ b/boost/algorithm/find_backward.hpp
@@ -0,0 +1,97 @@
+/*
+   Copyright (c) T. Zachary Laine 2018.
+
+   Distributed under the Boost Software License, Version 1.0. (See accompanying
+   file LICENSE10.txt or copy at http://www.boost.org/LICENSE10.txt)
+*/
+#ifndef BOOST_ALGORITHM_FIND_BACKWARD_HPP
+#define BOOST_ALGORITHM_FIND_BACKWARD_HPP
+
+#include <boost/config.hpp>
+#include <boost/range/begin.hpp>
+#include <boost/range/end.hpp>
+
+#include <utility>
+
+
+namespace boost { namespace algorithm {
+
+template<typename BidiIter, typename T>
+BOOST_CXX14_CONSTEXPR
+BidiIter find_backward(BidiIter first, BidiIter last, const T & x)
+{
+    BidiIter it = last;
+    while (it != first) {
+        if (*--it == x)
+            return it;
+    }
+    return last;
+}
+
+template<typename Range, typename T>
+BOOST_CXX14_CONSTEXPR
+typename boost::range_iterator<Range>::type find_backward(Range & range, const T & x)
+{
+    return ::boost::algorithm::find_backward(boost::begin(range), boost::end(range), x);
+}
+
+template<typename BidiIter, typename T>
+BOOST_CXX14_CONSTEXPR
+BidiIter find_not_backward(BidiIter first, BidiIter last, const T & x)
+{
+    BidiIter it = last;
+    while (it != first) {
+        if (*--it != x)
+            return it;
+    }
+    return last;
+}
+
+template<typename Range, typename T>
+BOOST_CXX14_CONSTEXPR
+typename boost::range_iterator<Range>::type find_not_backward(Range & range, const T & x)
+{
+    return ::boost::algorithm::find_not_backward(boost::begin(range), boost::end(range), x);
+}
+
+template<typename BidiIter, typename Pred>
+BOOST_CXX14_CONSTEXPR
+BidiIter find_if_backward(BidiIter first, BidiIter last, Pred p)
+{
+    BidiIter it = last;
+    while (it != first) {
+        if (p(*--it))
+            return it;
+    }
+    return last;
+}
+
+template<typename Range, typename Pred>
+BOOST_CXX14_CONSTEXPR
+typename boost::range_iterator<Range>::type find_if_backward(Range & range, Pred p)
+{
+    return ::boost::algorithm::find_if_backward(boost::begin(range), boost::end(range), p);
+}
+
+template<typename BidiIter, typename Pred>
+BOOST_CXX14_CONSTEXPR
+BidiIter find_if_not_backward(BidiIter first, BidiIter last, Pred p)
+{
+    BidiIter it = last;
+    while (it != first) {
+        if (!p(*--it))
+            return it;
+    }
+    return last;
+}
+
+template<typename Range, typename Pred>
+BOOST_CXX14_CONSTEXPR
+typename boost::range_iterator<Range>::type find_if_not_backward(Range & range, Pred p)
+{
+    return ::boost::algorithm::find_if_not_backward(boost::begin(range), boost::end(range), p);
+}
+
+}} // namespace boost and algorithm
+
+#endif // BOOST_ALGORITHM_FIND_BACKWARD_HPP