61 lines
1 KiB
C++
61 lines
1 KiB
C++
#pragma once
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#include <AK/Optional.h>
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#include <AK/String.h>
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#include <AK/Vector.h>
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template<typename T>
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class History final {
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public:
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void push(const T& item);
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T current() const;
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void go_back();
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void go_forward();
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bool can_go_back() { return m_current > 0; }
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bool can_go_forward() { return m_current + 1 < m_items.size(); }
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void clear();
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private:
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Vector<T> m_items;
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int m_current { -1 };
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};
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template<typename T>
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inline void History<T>::push(const T& item)
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{
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m_items.shrink(m_current + 1);
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m_items.append(item);
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m_current++;
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}
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template<typename T>
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inline T History<T>::current() const
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{
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if (m_current == -1)
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return {};
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return m_items[m_current];
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}
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template<typename T>
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inline void History<T>::go_back()
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{
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ASSERT(can_go_back());
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m_current--;
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}
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template<typename T>
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inline void History<T>::go_forward()
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{
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ASSERT(can_go_forward());
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m_current++;
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}
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template<typename T>
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inline void History<T>::clear()
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{
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m_items = {};
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m_current = -1;
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}
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