RowIterator.h

 
// Taken from libpqxx and modified.
// The license for libpqxx can be found in the COPYING file.
 
#pragma once
 
#include <drogon/orm/Field.h>
#include <drogon/orm/Row.h>
 
namespace drogon
{
namespace orm
{
class ConstRowIterator : protected Field
{
  public:
    using pointer = const Field *;
    using reference = const Field &;
    using value_type = const Field;
    using size_type = Row::SizeType;
    using difference_type = Row::DifferenceType;
    using iterator_category = std::random_access_iterator_tag;
 
    // ConstRowIterator(const Field &t) noexcept : Field(t) {}
 
    pointer operator->()
    {
        return this;
    }
 
    reference operator*()
    {
        return *this;
    }
 
    ConstRowIterator operator++(int);
 
    ConstRowIterator &operator++()
    {
        ++column_;
        return *this;
    }
 
    ConstRowIterator operator--(int);
 
    ConstRowIterator &operator--()
    {
        --column_;
        return *this;
    }
 
    ConstRowIterator &operator+=(difference_type i)
    {
        column_ += i;
        return *this;
    }
 
    ConstRowIterator &operator-=(difference_type i)
    {
        column_ -= i;
        return *this;
    }
 
    bool operator==(const ConstRowIterator &other) const
    {
        return column_ == other.column_;
    }
 
    bool operator!=(const ConstRowIterator &other) const
    {
        return column_ != other.column_;
    }
 
    bool operator>(const ConstRowIterator &other) const
    {
        return column_ > other.column_;
    }
 
    bool operator<(const ConstRowIterator &other) const
    {
        return column_ < other.column_;
    }
 
    bool operator>=(const ConstRowIterator &other) const
    {
        return column_ >= other.column_;
    }
 
    bool operator<=(const ConstRowIterator &other) const
    {
        return column_ <= other.column_;
    }
 
  private:
    friend class Row;
 
    ConstRowIterator(const Row &r, SizeType column) noexcept : Field(r, column)
    {
    }
};
 
class ConstReverseRowIterator : private ConstRowIterator
{
  public:
    using super = ConstRowIterator;
    using iterator_type = ConstRowIterator;
    using iterator_type::difference_type;
    using iterator_type::iterator_category;
    using iterator_type::pointer;
    using iterator_type::reference;
 
    // using iterator_type::value_type;
 
    ConstReverseRowIterator(const ConstReverseRowIterator &rhs)
        : ConstRowIterator(rhs)
    {
    }
 
    explicit ConstReverseRowIterator(const ConstRowIterator &rhs)
        : ConstRowIterator(rhs)
    {
        super::operator--();
    }
 
    ConstRowIterator base() const noexcept;
 
    using iterator_type::operator->;
    using iterator_type::operator*;
 
    ConstReverseRowIterator operator++(int);
 
    ConstReverseRowIterator &operator++()
    {
        iterator_type::operator--();
        return *this;
    }
 
    ConstReverseRowIterator operator--(int);
 
    ConstReverseRowIterator &operator--()
    {
        iterator_type::operator++();
        return *this;
    }
 
    ConstReverseRowIterator &operator+=(difference_type i)
    {
        iterator_type::operator-=(i);
        return *this;
    }
 
    ConstReverseRowIterator &operator-=(difference_type i)
    {
        iterator_type::operator+=(i);
        return *this;
    }
 
    bool operator==(const ConstReverseRowIterator &other) const
    {
        return column_ == other.column_;
    }
 
    bool operator!=(const ConstReverseRowIterator &other) const
    {
        return column_ != other.column_;
    }
 
    bool operator>(const ConstReverseRowIterator &other) const
    {
        return column_ < other.column_;
    }
 
    bool operator<(const ConstReverseRowIterator &other) const
    {
        return column_ > other.column_;
    }
 
    bool operator>=(const ConstReverseRowIterator &other) const
    {
        return column_ <= other.column_;
    }
 
    bool operator<=(const ConstReverseRowIterator &other) const
    {
        return column_ >= other.column_;
    }
};
 
}  // namespace orm
}  // namespace drogon