author | alpar |
Fri, 03 Sep 2004 14:26:03 +0000 | |
changeset 797 | a76d8d52b25c |
child 921 | 818510fa3d99 |
permissions | -rw-r--r-- |
deba@701 | 1 |
// -*- mode:C++ -*- |
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#ifndef HUGO_INVALID_H |
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#define HUGO_INVALID_H |
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///\file |
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///\brief Definition of INVALID. |
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namespace hugo { |
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/// Dummy type to make it easier to make invalid iterators. |
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/// See \ref INVALID, how to use it. |
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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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/// Invalid iterators. |
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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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// 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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//extern Invalid INVALID; |
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//const Invalid &INVALID = *(Invalid *)0; |
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const Invalid INVALID = Invalid(); |
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} //namespace hugo |
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#endif |
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