整理

include/boost/container_hash/is_range.hpp

@@ -0,0 +1,41 @@
+// Copyright 2017 Peter Dimov.
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#ifndef BOOST_HASH_IS_RANGE_HPP_INCLUDED
+#define BOOST_HASH_IS_RANGE_HPP_INCLUDED
+
+#include <iterator>
+#include <type_traits>
+
+namespace boost
+{
+
+namespace hash_detail
+{
+
+template<class T> struct iterator_traits: std::iterator_traits<T> {};
+template<> struct iterator_traits< void* > {};
+template<> struct iterator_traits< void const* > {};
+
+template<class T, class It>
+    std::integral_constant< bool, !std::is_same<typename std::remove_cv<T>::type, typename iterator_traits<It>::value_type>::value >
+        is_range_check( It first, It last );
+
+template<class T> decltype( is_range_check<T>( std::declval<T const&>().begin(), std::declval<T const&>().end() ) ) is_range_( int );
+template<class T> std::false_type is_range_( ... );
+
+} // namespace hash_detail
+
+namespace container_hash
+{
+
+template<class T> struct is_range: decltype( hash_detail::is_range_<T>( 0 ) )
+{
+};
+
+} // namespace container_hash
+
+} // namespace boost
+
+#endif // #ifndef BOOST_HASH_IS_RANGE_HPP_INCLUDED