54 lines
1.5 KiB
C++
54 lines
1.5 KiB
C++
/*
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Copyright (c) 2019 yvt
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This file is part of OpenSpades.
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OpenSpades is free software: you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation, either version 3 of the License, or
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(at your option) any later version.
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OpenSpades is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with OpenSpades. If not, see <http://www.gnu.org/licenses/>.
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*/
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#pragma once
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#include <Core/Debug.h>
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#include <Core/RefCountedObject.h>
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namespace spades {
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/**
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* Represents an iterator object.
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*
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* At the initial state, it does not point any element. `MoveNext` must be
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* called first to move the iterator to the first element.
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*/
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template <class T> class Iterator : public RefCountedObject {
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public:
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/**
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* Get the current item.
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*/
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virtual T GetCurrent() = 0;
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/**
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* Advance the iterator.
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*
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* @return `true` if the iterator was successfully advanced to the next
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* element. `false` if it reached the end of the sequence.
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*/
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virtual bool MoveNext() = 0;
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};
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/** Represents an iterator that produces no elements. */
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template <class T> class EmptyIterator final : public Iterator<T> {
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public:
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T GetCurrent() override { SPUnreachable(); }
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bool MoveNext() override { return false; }
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};
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} // namespace spades
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