LList.H

Go to the documentation of this file.

/*---------------------------------------------------------------------------*\
  =========                 |
  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
   \\    /   O peration     | Website:  https://openfoam.org
    \\  /    A nd           | Copyright (C) 2011-2021 OpenFOAM Foundation
     \\/     M anipulation  |
-------------------------------------------------------------------------------
License
    This file is part of OpenFOAM.
 
    OpenFOAM 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.
 
    OpenFOAM 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 OpenFOAM.  If not, see <http://www.gnu.org/licenses/>.
 
Class
    Foam::LList
 
Description
    Template class for non-intrusive linked lists.
 
SourceFiles
    LList.C
    LListIO.C
 
\*---------------------------------------------------------------------------*/
 
#ifndef LList_H
#define LList_H
 
#include "label.H"
#include <initializer_list>
 
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
namespace Foam
{
 
class Istream;
class Ostream;
 
// Forward declaration of friend functions and operators
 
template<class LListBase, class T> class LList;
 
template<class LListBase, class T>
Istream& operator>>
(
    Istream&,
    LList<LListBase, T>&
);
 
template<class LListBase, class T>
Ostream& operator<<
(
    Ostream&,
    const LList<LListBase, T>&
);
 
 
/*---------------------------------------------------------------------------*\
                            Class LList Declaration
\*---------------------------------------------------------------------------*/
 
template<class LListBase, class T>
class LList
:
    public LListBase
{
 
public:
 
    // Forward declaration of STL iterators
 
        class iterator;
        friend class iterator;
 
        class const_iterator;
        friend class const_iterator;
 
 
    //- Link structure
    struct link
    :
        public LListBase::link
    {
        //- Stored object
        T obj_;
 
        //- Construct given object
        link(T a)
        :
            obj_(a)
        {}
    };
 
 
    // Constructors
 
        //- Null construct
        LList()
        {}
 
        //- Construct given initial T
        LList(T a)
        :
            LListBase(new link(a))
        {}
 
        //- Construct from Istream
        LList(Istream&);
 
        //- Copy constructor
        LList(const LList<LListBase, T>&);
 
        //- Move constructor
        LList(LList<LListBase, T>&&);
 
        //- Construct from an initialiser list
        LList(std::initializer_list<T>);
 
 
    //- Destructor
    ~LList();
 
 
    // Member Functions
 
        // Access
 
            //- Return the first entry added
            T& first()
            {
                return static_cast<link*>(LListBase::first())->obj_;
            }
 
            //- Return const access to the first entry added
            const T& first() const
            {
                return static_cast<const link*>(LListBase::first())->obj_;
            }
 
            //- Return the last entry added
            T& last()
            {
                return static_cast<link*>(LListBase::last())->obj_;
            }
 
            //- Return const access to the last entry added
            const T& last() const
            {
                return static_cast<const link*>(LListBase::last())->obj_;
            }
 
 
        // Edit
 
            //- Add at head of list
            void insert(const T& a)
            {
                LListBase::insert(new link(a));
            }
 
            //- Add at tail of list
            void append(const T& a)
            {
                LListBase::append(new link(a));
            }
 
            //- Remove and return head
            T removeHead()
            {
                link* elmtPtr = static_cast<link*>(LListBase::removeHead());
                T data = elmtPtr->obj_;
                delete elmtPtr;
                return data;
            }
 
            //- Remove and return element
            T remove(link* l)
            {
                link* elmtPtr = static_cast<link*>(LListBase::remove(l));
                T data = elmtPtr->obj_;
                delete elmtPtr;
                return data;
            }
 
            //- Remove and return element specified by iterator
            T remove(iterator& it)
            {
                link* elmtPtr = static_cast<link*>(LListBase::remove(it));
                T data = elmtPtr->obj_;
                delete elmtPtr;
                return data;
            }
 
            //- Delete contents of list
            void clear();
 
            //- Transfer the contents of the argument into this List
            //  and annul the argument list.
            void transfer(LList<LListBase, T>&);
 
 
    // Member Operators
 
        //- Assignment operator
        void operator=(const LList<LListBase, T>&);
 
        //- Move assignment operator
        void operator=(LList<LListBase, T>&&);
 
        //- Assignment to an initialiser list
        void operator=(std::initializer_list<T>);
 
 
    // STL type definitions
 
        //- Type of values the LList contains.
        typedef T value_type;
 
        //- Type that can be used for storing into value_type
        //  objects.
        typedef T& reference;
 
        //- Type that can be used for storing into constant
        //  LList::value_type objects.
        typedef const T& const_reference;
 
        //- The type that can represent the size of a LList.
        typedef label size_type;
 
 
    // STL iterator
 
        typedef typename LListBase::iterator LListBase_iterator;
 
        //- An STL-conforming iterator
        class iterator
        :
            public LListBase_iterator
        {
 
        public:
 
            //- Construct from base iterator
            iterator(LListBase_iterator baseIter)
            :
                LListBase_iterator(baseIter)
            {}
 
 
            // Member Operators
 
                T& operator*()
                {
                    return
                        static_cast<link&>
                        (LListBase_iterator::operator*()).obj_;
                }
 
                T& operator()()
                {
                    return operator*();
                }
 
                iterator& operator++()
                {
                    LListBase_iterator::operator++();
                    return *this;
                }
        };
 
        inline iterator begin()
        {
            return LListBase::begin();
        }
 
        inline const iterator& end()
        {
            return static_cast<const iterator&>(LListBase::end());
        }
 
 
    // STL const_iterator
 
        typedef typename LListBase::const_iterator LListBase_const_iterator;
 
        //- An STL-conforming const_iterator
        class const_iterator
        :
            public LListBase_const_iterator
        {
 
        public:
 
            //- Construct from base const_iterator
            const_iterator(LListBase_const_iterator baseIter)
            :
                LListBase_const_iterator(baseIter)
            {}
 
 
            //- Construct from base iterator
            const_iterator(LListBase_iterator baseIter)
            :
                LListBase_const_iterator(baseIter)
            {}
 
 
            // Member Operators
 
                const T& operator*()
                {
                    return
                        static_cast<const link&>
                        (LListBase_const_iterator::operator*()).obj_;
                }
 
                const T& operator()()
                {
                    return operator*();
                }
 
                const_iterator& operator++()
                {
                    LListBase_const_iterator::operator++();
                    return *this;
                }
        };
 
        inline const_iterator cbegin() const
        {
            return LListBase::cbegin();
        }
 
        inline const const_iterator& cend() const
        {
            return static_cast<const const_iterator&>(LListBase::cend());
        }
 
        inline const_iterator begin() const
        {
            return LListBase::begin();
        }
 
        inline const const_iterator& end() const
        {
            return static_cast<const const_iterator&>(LListBase::end());
        }
 
 
    // IOstream Operators
 
        friend Istream& operator>> <LListBase, T>
        (
            Istream&,
            LList<LListBase, T>&
        );
 
        friend Ostream& operator<< <LListBase, T>
        (
            Ostream&,
            const LList<LListBase, T>&
        );
};
 
 
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
} // End namespace Foam
 
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
#ifdef NoRepository
    #include "LList.C"
#endif
 
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
#endif
 
// ************************************************************************* //