整理

include/boost/range/size.hpp

@@ -0,0 +1,76 @@
+// Boost.Range library
+//
+//  Copyright Thorsten Ottosen 2003-2004. Use, modification and
+//  distribution is subject to the Boost Software License, Version
+//  1.0. (See accompanying file LICENSE_1_0.txt or copy at
+//  http://www.boost.org/LICENSE_1_0.txt)
+//
+// For more information, see http://www.boost.org/libs/range/
+//
+
+#ifndef BOOST_RANGE_SIZE_HPP
+#define BOOST_RANGE_SIZE_HPP
+
+#if defined(_MSC_VER)
+# pragma once
+#endif
+
+#include <boost/range/config.hpp>
+#include <boost/range/begin.hpp>
+#include <boost/range/end.hpp>
+#include <boost/range/size_type.hpp>
+#include <boost/range/detail/has_member_size.hpp>
+#include <boost/assert.hpp>
+#include <boost/cstdint.hpp>
+#include <boost/utility.hpp>
+
+namespace boost
+{
+    namespace range_detail
+    {
+
+        template<class SinglePassRange>
+        inline typename ::boost::enable_if<
+            has_member_size<SinglePassRange>,
+            typename range_size<const SinglePassRange>::type
+        >::type
+        range_calculate_size(const SinglePassRange& rng)
+        {
+            return rng.size();
+        }
+
+        template<class SinglePassRange>
+        inline typename disable_if<
+            has_member_size<SinglePassRange>,
+            typename range_size<const SinglePassRange>::type
+        >::type
+        range_calculate_size(const SinglePassRange& rng)
+        {
+            return std::distance(boost::begin(rng), boost::end(rng));
+        }
+    }
+
+    template<class SinglePassRange>
+    inline typename range_size<const SinglePassRange>::type
+    size(const SinglePassRange& rng)
+    {
+// Very strange things happen on some compilers that have the range concept
+// asserts disabled. This preprocessor condition is clearly redundant on a
+// working compiler but is vital for at least some compilers such as clang 4.2
+// but only on the Mac!
+#if BOOST_RANGE_ENABLE_CONCEPT_ASSERT == 1
+        BOOST_RANGE_CONCEPT_ASSERT((boost::SinglePassRangeConcept<SinglePassRange>));
+#endif
+
+#if !BOOST_WORKAROUND(BOOST_BORLANDC, BOOST_TESTED_AT(0x564)) && \
+    !BOOST_WORKAROUND(__GNUC__, < 3) \
+    /**/
+        using namespace range_detail;
+#endif
+
+        return range_calculate_size(rng);
+    }
+
+} // namespace 'boost'
+
+#endif