1 // -*- C++ -*- 2 3 // Copyright (C) 2005-2013 Free Software Foundation, Inc. 4 // 5 // This file is part of the GNU ISO C++ Library. This library is free 6 // software; you can redistribute it and/or modify it under the terms 7 // of the GNU General Public License as published by the Free Software 8 // Foundation; either version 3, or (at your option) any later 9 // version. 10 11 // This library is distributed in the hope that it will be useful, but 12 // WITHOUT ANY WARRANTY; without even the implied warranty of 13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 14 // General Public License for more details. 15 16 // Under Section 7 of GPL version 3, you are granted additional 17 // permissions described in the GCC Runtime Library Exception, version 18 // 3.1, as published by the Free Software Foundation. 19 20 // You should have received a copy of the GNU General Public License and 21 // a copy of the GCC Runtime Library Exception along with this program; 22 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see 23 // <http://www.gnu.org/licenses/>. 24 25 // Copyright (C) 2004 Ami Tavory and Vladimir Dreizin, IBM-HRL. 26 27 // Permission to use, copy, modify, sell, and distribute this software 28 // is hereby granted without fee, provided that the above copyright 29 // notice appears in all copies, and that both that copyright notice 30 // and this permission notice appear in supporting documentation. None 31 // of the above authors, nor IBM Haifa Research Laboratories, make any 32 // representation about the suitability of this software for any 33 // purpose. It is provided "as is" without express or implied 34 // warranty. 35 36 /** 37 * @file sample_update_policy.hpp 38 * Contains a sample policy for list update containers. 39 */ 40 41 #ifndef PB_DS_SAMPLE_UPDATE_POLICY_HPP 42 #define PB_DS_SAMPLE_UPDATE_POLICY_HPP 43 44 namespace __gnu_pbds 45 { 46 /// A sample list-update policy. 47 struct sample_update_policy 48 { 49 /// Default constructor. 50 sample_update_policy(); 51 52 /// Copy constructor. 53 sample_update_policy(const sample_update_policy&); 54 55 /// Swaps content. 56 inline void 57 swap(sample_update_policy& other); 58 59 protected: 60 /// Metadata on which this functor operates. 61 typedef some_metadata_type metadata_type; 62 63 /// Creates a metadata object. 64 metadata_type 65 operator()() const; 66 67 /// Decides whether a metadata object should be moved to the front 68 /// of the list. A list-update based containers object will call 69 /// this method to decide whether to move a node to the front of 70 /// the list. The method shoule return true if the node should be 71 /// moved to the front of the list. 72 bool 73 operator()(metadata_reference) const; 74 }; 75 } 76 #endif 77
