1 // -*- C++ -*- 2 3 // Copyright (C) 2005, 2006 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 2, 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 // You should have received a copy of the GNU General Public License 17 // along with this library; see the file COPYING. If not, write to 18 // the Free Software Foundation, 59 Temple Place - Suite 330, Boston, 19 // MA 02111-1307, USA. 20 21 // As a special exception, you may use this file as part of a free 22 // software library without restriction. Specifically, if other files 23 // instantiate templates or use macros or inline functions from this 24 // file, or you compile this file and link it with other files to 25 // produce an executable, this file does not by itself cause the 26 // resulting executable to be covered by the GNU General Public 27 // License. This exception does not however invalidate any other 28 // reasons why the executable file might be covered by the GNU General 29 // Public License. 30 31 // Copyright (C) 2004 Ami Tavory and Vladimir Dreizin, IBM-HRL. 32 33 // Permission to use, copy, modify, sell, and distribute this software 34 // is hereby granted without fee, provided that the above copyright 35 // notice appears in all copies, and that both that copyright notice 36 // and this permission notice appear in supporting documentation. None 37 // of the above authors, nor IBM Haifa Research Laboratories, make any 38 // representation about the suitability of this software for any 39 // purpose. It is provided "as is" without express or implied 40 // warranty. 41 42 /** 43 * @file sample_update_policy.hpp 44 * Contains a sample policy for list update containers. 45 */ 46 47 #ifndef PB_DS_SAMPLE_UPDATE_POLICY_HPP 48 #define PB_DS_SAMPLE_UPDATE_POLICY_HPP 49 50 // A sample list-update policy. 51 struct sample_update_policy 52 { 53 // Default constructor. 54 sample_update_policy(); 55 56 // Copy constructor. 57 sample_update_policy(const sample_update_policy&); 58 59 // Swaps content. 60 inline void 61 swap(sample_update_policy& other); 62 63 protected: 64 // Metadata on which this functor operates. 65 typedef some_metadata_type metadata_type; 66 67 // Creates a metadata object. 68 metadata_type 69 operator()() const; 70 71 // Decides whether a metadata object should be moved to the front of 72 // the list. A list-update based containers object will call this 73 // method to decide whether to move a node to the front of the 74 // list. The method shoule return true if the node should be moved 75 // to the front of the list. 76 bool 77 operator()(metadata_reference) const; 78 }; 79 80 #endif 81