VectorOfAbstract.h

/*
 * (C) Copyright 2013 ECMWF.
 *
 * This software is licensed under the terms of the Apache Licence Version 2.0
 * which can be obtained at http://www.apache.org/licenses/LICENSE-2.0.
 * In applying this licence, ECMWF does not waive the privileges and immunities
 * granted to it by virtue of its status as an intergovernmental organisation
 * nor does it submit to any jurisdiction.
 */


#pragma once

#include <memory>
#include <vector>

#include "atlas/library/config.h"

namespace atlas {
namespace util {

//------------------------------------------------------------------------------------------------------

template <typename BaseIterator>
class DereferenceIterator : DOXYGEN_HIDE( public BaseIterator ) {
public:
    using value_type = typename BaseIterator::value_type::element_type;
    using pointer    = value_type*;
    using reference  = value_type&;

    DereferenceIterator( const BaseIterator& other ) : BaseIterator( other ) {}

    reference operator*() const { return *( this->BaseIterator::operator*() ); }
    pointer operator->() const { return this->BaseIterator::operator*().get(); }
    reference operator[]( size_t n ) const { return *( this->BaseIterator::operator[]( n ) ); }
};

//------------------------------------------------------------------------------------------------------

template <typename Iterator>
DereferenceIterator<Iterator> make_dereference_iterator( Iterator t ) {
    return DereferenceIterator<Iterator>( t );
}

//------------------------------------------------------------------------------------------------------

template <typename Abstract>
class VectorOfAbstract {
public:
    using value_type      = Abstract;
    using container_type  = std::vector<std::unique_ptr<value_type> >;
    using const_reference = const value_type&;
    using reference       = const_reference;
    using const_iterator  = DereferenceIterator<typename container_type::const_iterator>;

public:
    VectorOfAbstract() = default;
    VectorOfAbstract( VectorOfAbstract&& other ) : container_( std::move( other.container_ ) ) {}

    const_iterator begin() const { return make_dereference_iterator( container_.begin() ); }
    const_iterator end() const { return make_dereference_iterator( container_.end() ); }
    const_reference operator[]( idx_t i ) const { return *container_[i]; }
    const_reference at( idx_t i ) const { return *container_[i]; }
    idx_t size() const { return container_.size(); }
    void reserve( size_t size ) { container_.reserve( size ); }
    template <typename... Args>
    void emplace_back( Args&&... args ) {
        container_.emplace_back( std::forward<Args>( args )... );
    }
    container_type& get() { return container_; }
    void clear() { return container_.clear(); }

private:
    container_type container_;
};

//------------------------------------------------------------------------------------------------------

}  // namespace util
}  // namespace atlas