Squashed 'third_party/boostorg/utility/' content from commit ebe4429
Change-Id: I8e6ee78273db31df18f99d29034f855ccc064551
git-subtree-dir: third_party/boostorg/utility
git-subtree-split: ebe44296ca698e333a09e8268ea8ccedb3886c4d
diff --git a/include/boost/utility/compare_pointees.hpp b/include/boost/utility/compare_pointees.hpp
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+// Copyright (C) 2003, Fernando Luis Cacciola Carballal.
+//
+// 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)
+//
+// See http://www.boost.org/libs/optional for documentation.
+//
+// You are welcome to contact the author at:
+// fernando_cacciola@hotmail.com
+//
+#ifndef BOOST_UTILITY_COMPARE_POINTEES_25AGO2003_HPP
+#define BOOST_UTILITY_COMPARE_POINTEES_25AGO2003_HPP
+
+#include<functional>
+
+namespace boost {
+
+// template<class OP> bool equal_pointees(OP const& x, OP const& y);
+// template<class OP> struct equal_pointees_t;
+//
+// Being OP a model of OptionalPointee (either a pointer or an optional):
+//
+// If both x and y have valid pointees, returns the result of (*x == *y)
+// If only one has a valid pointee, returns false.
+// If none have valid pointees, returns true.
+// No-throw
+template<class OptionalPointee>
+inline
+bool equal_pointees ( OptionalPointee const& x, OptionalPointee const& y )
+{
+ return (!x) != (!y) ? false : ( !x ? true : (*x) == (*y) ) ;
+}
+
+template<class OptionalPointee>
+struct equal_pointees_t
+{
+ typedef bool result_type;
+ typedef OptionalPointee first_argument_type;
+ typedef OptionalPointee second_argument_type;
+
+ bool operator() ( OptionalPointee const& x, OptionalPointee const& y ) const
+ { return equal_pointees(x,y) ; }
+} ;
+
+// template<class OP> bool less_pointees(OP const& x, OP const& y);
+// template<class OP> struct less_pointees_t;
+//
+// Being OP a model of OptionalPointee (either a pointer or an optional):
+//
+// If y has not a valid pointee, returns false.
+// ElseIf x has not a valid pointee, returns true.
+// ElseIf both x and y have valid pointees, returns the result of (*x < *y)
+// No-throw
+template<class OptionalPointee>
+inline
+bool less_pointees ( OptionalPointee const& x, OptionalPointee const& y )
+{
+ return !y ? false : ( !x ? true : (*x) < (*y) ) ;
+}
+
+template<class OptionalPointee>
+struct less_pointees_t
+{
+ typedef bool result_type;
+ typedef OptionalPointee first_argument_type;
+ typedef OptionalPointee second_argument_type;
+
+ bool operator() ( OptionalPointee const& x, OptionalPointee const& y ) const
+ { return less_pointees(x,y) ; }
+} ;
+
+} // namespace boost
+
+#endif
+