author | alpar |
Fri, 19 Aug 2005 12:09:21 +0000 | |
changeset 1644 | 62548b317e65 |
parent 1359 | 1581f961cfaa |
child 1836 | 1fee7c6b5129 |
permissions | -rw-r--r-- |
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/* -*- C++ -*- |
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* lemon/invalid.h - Part of LEMON, a generic C++ optimization library |
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* |
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* Copyright (C) 2005 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_INVALID_H |
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#define LEMON_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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/// Dummy type to make it easier to make invalid iterators. |
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|
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/// See \ref INVALID, how to use it. |
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|
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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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// It is also used to convert the \c INVALID constant to the |
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// node iterator that makes is possible to write |
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|
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//extern Invalid INVALID; |
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|
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//const Invalid &INVALID = *(Invalid *)0; |
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const Invalid INVALID = Invalid(); |
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|
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} //namespace lemon |
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|
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#endif |
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