tagged_integer.h

// Copyright (c) 2014, Nikolaos D. Bougalis <nikb@bougalis.net>
 
#pragma once
 
#include <xrpl/beast/hash/hash_append.h>
 
#include <boost/operators.hpp>
 
#include <iostream>
#include <type_traits>
 
namespace xrpl {
 
template <class Int, class Tag>
class tagged_integer : boost::totally_ordered<
                           tagged_integer<Int, Tag>,
                           boost::integer_arithmetic<
                               tagged_integer<Int, Tag>,
                               boost::bitwise<
                                   tagged_integer<Int, Tag>,
                                   boost::unit_steppable<
                                       tagged_integer<Int, Tag>,
                                       boost::shiftable<tagged_integer<Int, Tag>>>>>>
{
private:
    Int m_value;
 
public:
    using value_type = Int;
    using tag_type = Tag;
 
    tagged_integer() = default;
 
    template <
        class OtherInt,
        class = typename std::enable_if<
            std::is_integral<OtherInt>::value && sizeof(OtherInt) <= sizeof(Int)>::type>
    explicit constexpr tagged_integer(OtherInt value) noexcept : m_value(value)
    {
        static_assert(sizeof(tagged_integer) == sizeof(Int), "tagged_integer is adding padding");
    }
 
    bool
    operator<(tagged_integer const& rhs) const noexcept
    {
        return m_value < rhs.m_value;
    }
 
    bool
    operator==(tagged_integer const& rhs) const noexcept
    {
        return m_value == rhs.m_value;
    }
 
    tagged_integer&
    operator+=(tagged_integer const& rhs) noexcept
    {
        m_value += rhs.m_value;
        return *this;
    }
 
    tagged_integer&
    operator-=(tagged_integer const& rhs) noexcept
    {
        m_value -= rhs.m_value;
        return *this;
    }
 
    tagged_integer&
    operator*=(tagged_integer const& rhs) noexcept
    {
        m_value *= rhs.m_value;
        return *this;
    }
 
    tagged_integer&
    operator/=(tagged_integer const& rhs) noexcept
    {
        m_value /= rhs.m_value;
        return *this;
    }
 
    tagged_integer&
    operator%=(tagged_integer const& rhs) noexcept
    {
        m_value %= rhs.m_value;
        return *this;
    }
 
    tagged_integer&
    operator|=(tagged_integer const& rhs) noexcept
    {
        m_value |= rhs.m_value;
        return *this;
    }
 
    tagged_integer&
    operator&=(tagged_integer const& rhs) noexcept
    {
        m_value &= rhs.m_value;
        return *this;
    }
 
    tagged_integer&
    operator^=(tagged_integer const& rhs) noexcept
    {
        m_value ^= rhs.m_value;
        return *this;
    }
 
    tagged_integer&
    operator<<=(tagged_integer const& rhs) noexcept
    {
        m_value <<= rhs.m_value;
        return *this;
    }
 
    tagged_integer&
    operator>>=(tagged_integer const& rhs) noexcept
    {
        m_value >>= rhs.m_value;
        return *this;
    }
 
    tagged_integer
    operator~() const noexcept
    {
        return tagged_integer{~m_value};
    }
 
    tagged_integer
    operator+() const noexcept
    {
        return *this;
    }
 
    tagged_integer
    operator-() const noexcept
    {
        return tagged_integer{-m_value};
    }
 
    tagged_integer&
    operator++() noexcept
    {
        ++m_value;
        return *this;
    }
 
    tagged_integer&
    operator--() noexcept
    {
        --m_value;
        return *this;
    }
 
    explicit
    operator Int() const noexcept
    {
        return m_value;
    }
 
    friend std::ostream&
    operator<<(std::ostream& s, tagged_integer const& t)
    {
        s << t.m_value;
        return s;
    }
 
    friend std::istream&
    operator>>(std::istream& s, tagged_integer& t)
    {
        s >> t.m_value;
        return s;
    }
 
    friend std::string
    to_string(tagged_integer const& t)
    {
        return std::to_string(t.m_value);
    }
};
 
}  // namespace xrpl
 
namespace beast {
template <class Int, class Tag, class HashAlgorithm>
struct is_contiguously_hashable<xrpl::tagged_integer<Int, Tag>, HashAlgorithm>
    : public is_contiguously_hashable<Int, HashAlgorithm>
{
    explicit is_contiguously_hashable() = default;
};
 
}  // namespace beast