author | alpar |
Thu, 10 Aug 2006 14:56:36 +0000 | |
branch | lemon-1.0 |
changeset 2655 | 3aa8ee4853dc |
permissions | -rw-r--r-- |
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/* -*- C++ -*- |
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* |
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* This file is a part of LEMON, a generic C++ optimization library |
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* |
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* Copyright (C) 2003-2006 |
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* Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport |
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* (Egervary Research Group on Combinatorial Optimization, EGRES). |
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* |
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* Permission to use, modify and distribute this software is granted |
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* provided that this copyright notice appears in all copies. For |
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* precise terms see the accompanying LICENSE file. |
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* |
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* This software is provided "AS IS" with no warranty of any kind, |
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* express or implied, and with no claim as to its suitability for any |
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* purpose. |
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* |
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*/ |
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|
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#ifndef LEMON_BITS_INVALID_H |
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#define LEMON_BITS_INVALID_H |
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|
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///\file |
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///\brief Definition of INVALID. |
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|
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namespace lemon { |
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|
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/// \brief Dummy type to make it easier to make invalid iterators. |
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/// |
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/// See \ref INVALID for the usage. |
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struct Invalid { |
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public: |
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bool operator==(Invalid) { return true; } |
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bool operator!=(Invalid) { return false; } |
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bool operator< (Invalid) { return false; } |
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}; |
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|
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/// Invalid iterators. |
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|
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/// \ref Invalid is a global type that converts to each iterator |
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/// in such a way that the value of the target iterator will be invalid. |
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|
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//Some people didn't like this: |
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//const Invalid &INVALID = *(Invalid *)0; |
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|
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#ifdef LEMON_ONLY_TEMPLATES |
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const Invalid INVALID = Invalid(); |
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#else |
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extern const Invalid INVALID; |
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#endif |
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|
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} //namespace lemon |
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|
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#endif |
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