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// Null Node |
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// |
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// Douglas Thrift |
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// |
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// $Id$ |
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|
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#ifndef _NullNode_hpp_ |
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#define _NullNode_hpp_ |
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|
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#include "Node.hpp" |
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|
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template<typename Type> |
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class NullNode : public Node<Type> |
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{ |
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public: |
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void setNext(NullNode<Type>* next) { this->next = dynamic_cast<Node<Type>*>(next); } |
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void setPrevious(NullNode<Type>* previous) { this->previous = dynamic_cast<Node<Type>*>(previous); } |
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bool contains(const Type& value, Node<Type>* end, bool forward); |
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void remove(const Type& value, Node<Type>* end, bool forward); |
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void accept(Visitor<Type>* visitor, Node<Type>* end, bool forward); |
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}; |
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|
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template<typename Type> |
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bool NullNode<Type>::contains(const Type& value, Node<Type>* end, bool forward) |
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{ |
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Node<Type>* another = forward ? Node<Type>::next : Node<Type>::previous; |
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|
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if (end == this) return false; else return another->contains(value, end, forward); |
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} |
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|
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template<typename Type> |
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void NullNode<Type>::remove(const Type& value, Node<Type>* end, bool forward) |
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{ |
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Node<Type>* another = forward ? Node<Type>::next : Node<Type>::previous; |
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|
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if (end != this) another->remove(value, end, forward); |
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} |
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|
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template<typename Type> |
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void NullNode<Type>::accept(Visitor<Type>* visitor, Node<Type>* end, bool forward) |
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{ |
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Node<Type>* another = forward ? Node<Type>::next : Node<Type>::previous; |
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|
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if (end != this) another->accept(visitor, end, forward); |
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} |
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|
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#endif // _NullNode_hpp_ |
