Implement the C++17 new algorithms

include/boost/algorithm/cxx17/inclusive_scan.hpp

@@ -0,0 +1,60 @@
+/*
+   Copyright (c) Marshall Clow 2017.
+
+   Distributed under the Boost Software License, Version 1.0. (See accompanying
+   file LICENSE10.txt or copy at http://www.boost.org/LICENSE10.txt)
+*/
+
+/// \file  transform_reduce.hpp
+/// \brief Combine the (transformed) elements of a sequence (or two) into a single value.
+/// \author Marshall Clow
+
+#ifndef BOOST_ALGORITHM_TRANSFORM_REDUCE_HPP
+#define BOOST_ALGORITHM_TRANSFORM_REDUCE_HPP
+
+#include <functional>     // for std::plus
+#include <iterator>       // for std::iterator_traits
+
+#include <boost/range/begin.hpp>
+#include <boost/range/end.hpp>
+#include <boost/range/value_type.hpp>
+
+namespace boost { namespace algorithm {
+
+template<class InputIterator, class OutputIterator, class T, class BinaryOperation>
+OutputIterator inclusive_scan(InputIterator first, InputIterator last,
+                              OutputIterator result, BinaryOperation bOp, T init)
+{
+    for (; first != last; ++first, (void) ++result) {
+        init = bOp(init, *first);
+        *result = init;
+        }
+    return result;
+}
+
+
+template<class InputIterator, class OutputIterator, class BinaryOperation>
+OutputIterator inclusive_scan(InputIterator first, InputIterator last,
+                              OutputIterator result, BinaryOperation bOp)
+{
+    if (first != last) {
+        typename std::iterator_traits<InputIterator>::value_type init = *first;
+        *result++ = init;
+        if (++first != last)
+            return inclusive_scan(first, last, result, bOp, init);
+        }
+
+    return result;
+}
+
+template<class InputIterator, class OutputIterator>
+OutputIterator inclusive_scan(InputIterator first, InputIterator last,
+                   OutputIterator result)
+{
+    typedef typename std::iterator_traits<InputIterator>::value_type VT;
+    return inclusive_scan(first, last, result, std::plus<VT>());
+}
+
+}} // namespace boost and algorithm
+
+#endif // BOOST_ALGORITHM_TRANSFORM_REDUCE_HPP