add ptr_value container

alib2std/src/alib/ptr_value

+#include <extensions/container/ptr_value.hpp>

alib2std/src/extensions/container/ptr_value.hpp

+/*
+ * ptr_tuple.hpp
+ *
+ * This file is part of Algorithms library toolkit.
+ * Copyright (C) 2017 Jan Travnicek (jan.travnicek@fit.cvut.cz)
+
+ * Algorithms library toolkit is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+
+ * Algorithms library toolkit is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+
+ * You should have received a copy of the GNU General Public License
+ * along with Algorithms library toolkit.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Created on: Feb 28, 2014
+ * Author: Jan Travnicek
+ */
+
+#ifndef __PTR_VALUE_HPP_
+#define __PTR_VALUE_HPP_
+
+#include <ostream>
+#include <sstream>
+#include <string>
+
+#include <extensions/iterator.hpp>
+#include <extensions/compare.hpp>
+#include <extensions/clone.hpp>
+
+#include <extensions/common/tuple_common.hpp>
+
+namespace ext {
+
+/**
+ * \brief
+ * Class representing wrapper of dynamically allocated object behaving like rvalue reference.
+ *
+ * The class takes ownership of the dynamically allocated object
+ *
+ * \tparam the type of value wrapped
+ */
+template < class T >
+class ptr_value {
+	/**
+	 * \brief
+	 * Owned dynamically allocated object
+	 */
+	T * m_data;
+
+public:
+	/**
+	 * \brief
+	 * Constructor of the ptr_value from dynaically allocated object. The class will take ownerhip of the pointer.
+	 */
+	explicit ptr_value ( const T & value ) : m_data ( ext::clone ( value ) ) {
+
+	}
+
+	/**
+	 * \brief
+	 * Constructor of the ptr_value from dynaically allocated object. The class will take ownerhip of the pointer.
+	 */
+	explicit ptr_value ( T && value ) : m_data ( ext::clone ( std::forward < T > ( value ) ) ) {
+
+	}
+
+	/**
+	 * \brief
+	 * User conversion constructor from ptr_value for type U where T is its predecessor
+	 *
+	 * \tparam U the subtype of T
+	 *
+	 * \param other the other instance
+	 */
+	template < class U >
+	ptr_value ( ptr_value < U > && other ) : m_data ( other.m_data ) {
+		other.m_data = nullptr;
+	}
+
+	/**
+	 * \brief
+	 * Copy construction will clone the pointer referenced value in source instance to create new one for the constructed object.
+	 *
+	 * \param other the other instance
+	 */
+	ptr_value ( const ptr_value & other ) : m_data ( ext::clone ( other.m_data ) ) {
+
+	}
+
+	/**
+	 * \brief
+	 * Move construction will transfer ownership of the pointer from source instance to newly created one.
+	 *
+	 * \param other the other instance
+	 */
+	ptr_value ( ptr_value && other ) : m_data ( other.m_data ) {
+		other.m_data = nullptr;
+	};
+
+	/**
+	 * \brief
+	 * Copy assignment will clone the pointer referenced value in source instance to create new one for the constructed object.
+	 *
+	 * \param other the other instance
+	 */
+	ptr_value & operator = ( const ptr_value & other ) {
+		delete m_data;
+		m_data = ext::clone ( other.m_data );
+		return * this;
+	}
+
+	/**
+	 * \param
+	 * Move assignment will swap holded pointers between the two instances.
+	 *
+	 * \param other the other instance.
+	 */
+	ptr_value & operator = ( ptr_value && other ) {
+		using std::swap;
+
+		swap ( m_data, other.m_data );
+
+		return *this;
+	}
+
+	/**
+	 * \brief
+	 * Destructor will free the owned instance.
+	 */
+	~ptr_value ( ) {
+		delete m_data;
+	}
+
+	/**
+	 * \brief
+	 * Arrow operator to chain dereference.
+	 *
+	 * \return the owned pointer
+	 */
+	T * operator ->( ) && {
+		return m_data;
+	}
+
+	/**
+	 * \brief
+	 * Arrow operator to chain dereference.
+	 *
+	 * \return the owned pointer
+	 */
+	T * operator ->( ) & {
+		return m_data;
+	}
+
+	/**
+	 * \brief
+	 * Arrow operator to chain dereference.
+	 *
+	 * \return the owned pointer
+	 */
+	const T * operator ->( ) const & {
+		return m_data;
+	}
+
+	/**
+	 * \brief
+	 * Allow automatic cast to rvalue reference which can be itself binded to const reference.
+	 *
+	 * \return the holded value
+	 */
+	operator T && ( ) && {
+		return std::move ( * m_data );
+	}
+
+	/**
+	 * \brief
+	 * Getter of the holded value.
+	 *
+	 * \return constant reference to the holded value
+	 */
+	const T & get ( ) const {
+		return * m_data;
+	}
+
+	template < class U >
+	friend class ptr_value;
+};
+
+} /* namespace ext */
+
+#endif /* __PTR_VALUE_HPP_ */