[WIP] Checkpoint

- That makes minMantissa 2^63/10+1.
- Simplifies many of the existing operations, and removes the need for
  the accessors (mantissa() & exponent()) to do any math.

include/xrpl/basics/Number.h

@@ -36,18 +36,37 @@ class Number;
 std::string
 to_string(Number const& amount);
 
+/** Returns a rough estimate of log10(value).
+ *
+ * The return value is a pair (log, rem), where log is the estimated log10,
+ * and rem is value divided by 10^log. If rem is 1, then value is an exact
+ * power of ten, and log is the exact log10(value).
+ *
+ * This function only works for positive values.
+ */
+template <typename T>
+constexpr std::pair<int, T>
+logTenEstimate(T value)
+{
+    int log = 0;
+    T remainder = value;
+    while (value >= 10)
+    {
+        if (value % 10 == 0)
+            remainder = remainder / 10;
+        value /= 10;
+        ++log;
+    }
+    return {log, remainder};
+}
+
 template <typename T>
 constexpr std::optional<int>
 logTen(T value)
 {
-    int log = 0;
-    while (value >= 10 && value % 10 == 0)
-    {
-        value /= 10;
-        ++log;
-    }
-    if (value == 1)
-        return log;
+    auto const est = logTenEstimate(value);
+    if (est.second == 1)
+        return est.first;
     return std::nullopt;
 }
 
@@ -61,12 +80,10 @@ isPowerOfTen(T value)
 /** MantissaRange defines a range for the mantissa of a normalized Number.
  *
  * The mantissa is in the range [min, max], where
- * * min is a power of 10, and
- * * max = min * 10 - 1.
  *
  * The mantissa_scale enum indicates whether the range is "small" or "large".
  * This intentionally restricts the number of MantissaRanges that can be
- * instantiated to two: one for each scale.
+ * used to two: one for each scale.
  *
  * The "small" scale is based on the behavior of STAmount for IOUs. It has a min
  * value of 10^15, and a max value of 10^16-1. This was sufficient for
@@ -80,8 +97,8 @@ isPowerOfTen(T value)
  * "large" scale.
  *
  * The "large" scale is intended to represent all values that can be represented
- * by an STAmount - IOUs, XRP, and MPTs. It has a min value of 10^18, and a max
- * value of 10^19-1.
+ * by an STAmount - IOUs, XRP, and MPTs. It has a min value of 2^63/10+1
+ * (truncated), and a max value of 2^63-1.
  *
  * Note that if the mentioned amendments are eventually retired, this class
  * should be left in place, but the "small" scale option should be removed. This
@@ -93,28 +110,42 @@ struct MantissaRange
     enum mantissa_scale { small, large };
 
     explicit constexpr MantissaRange(mantissa_scale scale_)
-        : min(getMin(scale_))
-        , max(min * 10 - 1)
-        , log(logTen(min).value_or(-1))
+        : max(getMax(scale_))
+        , min(computeMin(max))
+        , referenceMin(getReferenceMin(scale_, min))
+        , log(computeLog(min))
         , scale(scale_)
     {
+        // Since this is constexpr, if any of these throw, it won't compile
+        if (min * 10 <= max)
+            throw std::out_of_range("min * 10 <= max");
+        if (max / 10 >= min)
+            throw std::out_of_range("max / 10 >= min");
+        if ((min - 1) * 10 > max)
+            throw std::out_of_range("(min - 1) * 10 > max");
+        // This is a little hacky
+        if ((max + 10) / 10 < min)
+            throw std::out_of_range("(max + 10) / 10 < min");
     }
 
-    rep min;
     rep max;
+    rep min;
+    // This is not a great name. Used to determine if mantissas are in range,
+    // but have fewer digits than max
+    rep referenceMin;
     int log;
     mantissa_scale scale;
 
 private:
     static constexpr rep
-    getMin(mantissa_scale scale_)
+    getMax(mantissa_scale scale)
     {
-        switch (scale_)
+        switch (scale)
         {
             case small:
-                return 1'000'000'000'000'000ULL;
+                return 9'999'999'999'999'999ULL;
             case large:
-                return 1'000'000'000'000'000'000ULL;
+                return std::numeric_limits<std::int64_t>::max();
             default:
                 // Since this can never be called outside a non-constexpr
                 // context, this throw assures that the build fails if an
@@ -122,6 +153,33 @@ private:
                 throw std::runtime_error("Unknown mantissa scale");
         }
     }
+
+    static constexpr rep
+    computeMin(rep max)
+    {
+        return max / 10 + 1;
+    }
+
+    static constexpr rep
+    getReferenceMin(mantissa_scale scale, rep min)
+    {
+        switch (scale)
+        {
+            case large:
+                return 1'000'000'000'000'000'000ULL;
+            default:
+                if (isPowerOfTen(min))
+                    return min;
+                throw std::runtime_error("Unknown/bad mantissa scale");
+        }
+    }
+
+    static constexpr rep
+    computeLog(rep min)
+    {
+        auto const estimate = logTenEstimate(min);
+        return estimate.first + (estimate.second == 1 ? 0 : 1);
+    }
 };
 
 // Like std::integral, but only 64-bit integral types.
@@ -156,9 +214,7 @@ concept Integral64 =
  *   1. Normalization can be disabled by using the "unchecked" ctor tag. This
  *      should only be used at specific conversion points, some constexpr
  *      values, and in unit tests.
- *   2. The max of the "large" range, 10^19-1, is the largest 10^X-1 value that
- *      fits in an unsigned 64-bit number. (10^19-1 < 2^64-1 and
- *      10^20-1 > 2^64-1). This avoids under- and overflows.
+ *   2. The max of the "large" range, 2^63-1, TODO: explain the large range.
  *
  * ---- External Interface ----
  *
@@ -172,7 +228,7 @@ concept Integral64 =
  *
  * Note:
  *   1. 2^63-1 is between 10^18 and 10^19-1, which are the limits of the "large"
- *      mantissa range.
+ *      mantissa range. TODO: update this explanation.
  *   2. The functions mantissa() and exponent() return the external view of the
  *      Number value, specifically using a signed 63-bit mantissa. This may
  *      require altering the internal representation to fit into that range
@@ -232,8 +288,7 @@ class Number
     using rep = std::int64_t;
     using internalrep = MantissaRange::rep;
 
-    bool negative_{false};
-    internalrep mantissa_{0};
+    rep mantissa_{0};
     int exponent_{std::numeric_limits<int>::lowest()};
 
 public:
@@ -241,9 +296,11 @@ public:
     constexpr static int minExponent = -32768;
     constexpr static int maxExponent = 32768;
 
+#if MAXREP
     constexpr static internalrep maxRep = std::numeric_limits<rep>::max();
     static_assert(maxRep == 9'223'372'036'854'775'807);
     static_assert(-maxRep == std::numeric_limits<rep>::min() + 1);
+#endif
 
     // May need to make unchecked private
     struct unchecked
@@ -329,7 +386,7 @@ public:
     friend constexpr bool
     operator==(Number const& x, Number const& y) noexcept
     {
-        return x.negative_ == y.negative_ && x.mantissa_ == y.mantissa_ &&
+        return x.mantissa_ == y.mantissa_ &&
             x.exponent_ == y.exponent_;
     }
 
@@ -344,8 +401,8 @@ public:
     {
         // If the two amounts have different signs (zero is treated as positive)
         // then the comparison is true iff the left is negative.
-        bool const lneg = x.negative_;
-        bool const rneg = y.negative_;
+        bool const lneg = x.mantissa_ < 0;
+        bool const rneg = y.mantissa_ < 0;
 
         if (lneg != rneg)
             return lneg;
@@ -373,7 +430,7 @@ public:
     constexpr int
     signum() const noexcept
     {
-        return negative_ ? -1 : (mantissa_ ? 1 : 0);
+        return mantissa_ < 0 ? -1 : (mantissa_ ? 1 : 0);
     }
 
     Number
@@ -476,16 +533,31 @@ private:
     static_assert(isPowerOfTen(smallRange.min));
     static_assert(smallRange.min == 1'000'000'000'000'000LL);
     static_assert(smallRange.max == 9'999'999'999'999'999LL);
+    static_assert(smallRange.referenceMin == smallRange.min);
     static_assert(smallRange.log == 15);
+#if MAXREP
     static_assert(smallRange.min < maxRep);
     static_assert(smallRange.max < maxRep);
+#endif
     constexpr static MantissaRange largeRange{MantissaRange::large};
-    static_assert(isPowerOfTen(largeRange.min));
-    static_assert(largeRange.min == 1'000'000'000'000'000'000ULL);
-    static_assert(largeRange.max == internalrep(9'999'999'999'999'999'999ULL));
+    static_assert(!isPowerOfTen(largeRange.min));
+    static_assert(largeRange.min == 922'337'203'685'477'581ULL);
+    static_assert(largeRange.max == internalrep(9'223'372'036'854'775'807ULL));
+    static_assert(largeRange.max == std::numeric_limits<rep>::max());
+    static_assert(largeRange.referenceMin == 1'000'000'000'000'000'000ULL);
     static_assert(largeRange.log == 18);
+    // There are 2 values that will not fit in largeRange without some extra
+    // work
+    // * 9223372036854775808
+    // * 9223372036854775809
+    // They both end up < min, but with a leftover. If they round up, everything
+    // will be fine. If they don't, well need to bring them up into range.
+    // Guard::bringIntoRange handles this situation.
+
+#if MAXREP
     static_assert(largeRange.min < maxRep);
     static_assert(largeRange.max > maxRep);
+#endif
 
     // The range for the mantissa when normalized.
     // Use reference_wrapper to avoid making copies, and prevent accidentally
@@ -514,8 +586,8 @@ private:
     friend void
     doNormalize(
         bool& negative,
-        T& mantissa_,
-        int& exponent_,
+        T& mantissa,
+        int& exponent,
         MantissaRange::rep const& minMantissa,
         MantissaRange::rep const& maxMantissa);
 
@@ -535,7 +607,21 @@ private:
     static internalrep
     externalToInternal(rep mantissa);
 
+    // Safely convert Number to the internal rep where the mantissa always has
+    // the same number of digits
+    template <class Rep = internalrep>
+    std::tuple<bool, Rep, int>
+    toInternal() const;
+
+    // Set the Number from an internal representation
+    template <class Rep = internalrep>
+    void
+    fromInternal(bool negative, Rep mantissa, int exponent);
+
     class Guard;
+
+public:
+    constexpr static internalrep largestMantissa = largeRange.max;
 };
 
 inline constexpr Number::Number(
@@ -543,7 +629,7 @@ inline constexpr Number::Number(
     internalrep mantissa,
     int exponent,
     unchecked) noexcept
-    : negative_(negative), mantissa_{mantissa}, exponent_{exponent}
+    : mantissa_{(negative ? -1 : 1) * static_cast<rep>(mantissa)}, exponent_{exponent}
 {
 }
 
@@ -562,9 +648,10 @@ inline Number::Number(
     internalrep mantissa,
     int exponent,
     normalized)
-    : Number(negative, mantissa, exponent, unchecked{})
 {
-    normalize();
+    auto const& range = range_.get();
+    normalize(negative, mantissa, exponent, range.min, range.max);
+    fromInternal(negative, mantissa, exponent);
 }
 
 inline Number::Number(internalrep mantissa, int exponent, normalized)
@@ -589,17 +676,7 @@ inline Number::Number(rep mantissa) : Number{mantissa, 0}
 inline constexpr Number::rep
 Number::mantissa() const noexcept
 {
-    auto m = mantissa_;
-    if (m > maxRep)
-    {
-        XRPL_ASSERT_PARTS(
-            !isnormal() || (m % 10 == 0 && m / 10 <= maxRep),
-            "xrpl::Number::mantissa",
-            "large normalized mantissa has no remainder");
-        m /= 10;
-    }
-    auto const sign = negative_ ? -1 : 1;
-    return sign * static_cast<Number::rep>(m);
+    return mantissa_;
 }
 
 /** Returns the exponent of the external view of the Number.
@@ -610,16 +687,7 @@ Number::mantissa() const noexcept
 inline constexpr int
 Number::exponent() const noexcept
 {
-    auto e = exponent_;
-    if (mantissa_ > maxRep)
-    {
-        XRPL_ASSERT_PARTS(
-            !isnormal() || (mantissa_ % 10 == 0 && mantissa_ / 10 <= maxRep),
-            "xrpl::Number::exponent",
-            "large normalized mantissa has no remainder");
-        ++e;
-    }
-    return e;
+    return exponent_;
 }
 
 inline constexpr Number
@@ -634,7 +702,7 @@ Number::operator-() const noexcept
     if (mantissa_ == 0)
         return Number{};
     auto x = *this;
-    x.negative_ = !x.negative_;
+    x.mantissa_ = -1 * x.mantissa_;
     return x;
 }
 
@@ -715,34 +783,33 @@ Number::min() noexcept
 inline Number
 Number::max() noexcept
 {
-    return Number{
-        false, std::min(range_.get().max, maxRep), maxExponent, unchecked{}};
+    return Number{false, range_.get().max, maxExponent, unchecked{}};
 }
 
 inline Number
 Number::lowest() noexcept
 {
-    return Number{
-        true, std::min(range_.get().max, maxRep), maxExponent, unchecked{}};
+    return Number{true, range_.get().max, maxExponent, unchecked{}};
 }
 
 inline bool
 Number::isnormal() const noexcept
 {
     MantissaRange const& range = range_;
-    auto const abs_m = mantissa_;
+    auto const abs_m = mantissa_ < 0 ? -mantissa_ : mantissa_;
+
     return *this == Number{} ||
-        (range.min <= abs_m && abs_m <= range.max &&
-         (abs_m <= maxRep || abs_m % 10 == 0) && minExponent <= exponent_ &&
-         exponent_ <= maxExponent);
+        (range.min <= abs_m && abs_m <= range.max &&  //
+         minExponent <= exponent_ && exponent_ <= maxExponent);
 }
 
 template <Integral64 T>
 std::pair<T, int>
 Number::normalizeToRange(T minMantissa, T maxMantissa) const
 {
-    bool negative = negative_;
-    internalrep mantissa = mantissa_;
+    bool negative = mantissa_ < 0;
+    auto const sign = negative ? -1 : 1;
+    internalrep mantissa = sign * mantissa_;
     int exponent = exponent_;
 
     if constexpr (std::is_unsigned_v<T>)
@@ -752,8 +819,7 @@ Number::normalizeToRange(T minMantissa, T maxMantissa) const
             "Number is non-negative for unsigned range.");
     Number::normalize(negative, mantissa, exponent, minMantissa, maxMantissa);
 
-    auto const sign = negative ? -1 : 1;
-    return std::make_pair(static_cast<T>(sign * mantissa), exponent);
+    return std::make_pair(sign * static_cast<T>(mantissa), exponent);
 }
 
 inline constexpr Number

include/xrpl/protocol/Protocol.h

@@ -252,7 +252,7 @@ std::size_t constexpr maxMPTokenMetadataLength = 1024;
 
 /** The maximum amount of MPTokenIssuance */
 std::uint64_t constexpr maxMPTokenAmount = 0x7FFF'FFFF'FFFF'FFFFull;
-static_assert(Number::maxRep >= maxMPTokenAmount);
+static_assert(Number::largestMantissa >= maxMPTokenAmount);
 
 /** The maximum length of Data payload */
 std::size_t constexpr maxDataPayloadLength = 256;

include/xrpl/protocol/SystemParameters.h

@@ -43,7 +43,7 @@ systemName()
 /** Number of drops in the genesis account. */
 constexpr XRPAmount INITIAL_XRP{100'000'000'000 * DROPS_PER_XRP};
 static_assert(INITIAL_XRP.drops() == 100'000'000'000'000'000);
-static_assert(Number::maxRep >= INITIAL_XRP.drops());
+static_assert(Number::largestMantissa >= INITIAL_XRP.drops());
 
 /** Returns true if the amount does not exceed the initial XRP in existence. */
 inline bool

src/libxrpl/basics/Number.cpp

@@ -257,7 +257,7 @@ Number::Guard::bringIntoRange(
     {
         constexpr Number zero = Number{};
 
-        negative = zero.negative_;
+        negative = false;
         mantissa = zero.mantissa_;
         exponent = zero.exponent_;
     }
@@ -279,7 +279,7 @@ Number::Guard::doRoundUp(
         ++mantissa;
         // Ensure mantissa after incrementing fits within both the
         // min/maxMantissa range and is a valid "rep".
-        if (mantissa > maxMantissa || mantissa > maxRep)
+        if (mantissa > maxMantissa)
         {
             mantissa /= 10;
             ++exponent;
@@ -318,7 +318,7 @@ Number::Guard::doRound(rep& drops, std::string location)
     auto r = round();
     if (r == 1 || (r == 0 && (drops & 1) == 1))
     {
-        if (drops >= maxRep)
+        if (drops >= maxMantissa())
         {
             static_assert(sizeof(internalrep) == sizeof(rep));
             // This should be impossible, because it's impossible to represent
@@ -360,12 +360,65 @@ Number::externalToInternal(rep mantissa)
     return static_cast<internalrep>(-temp);
 }
 
+template <class Rep>
+std::tuple<bool, Rep, int>
+Number::toInternal() const
+{
+    auto exponent = exponent_;
+    bool const negative = mantissa_ < 0;
+    auto const sign = negative ? -1 : 1;
+    Rep mantissa = static_cast<Rep>(sign * mantissa_);
+
+    auto const& range = Number::range_.get();
+    auto const referenceMin = range.referenceMin;
+    auto const minMantissa = range.min;
+
+    if (mantissa != 0 && mantissa >= minMantissa && mantissa < referenceMin)
+    {
+        // Ensure the mantissa has the correct number of digits
+        mantissa *= 10;
+        --exponent;
+        XRPL_ASSERT_PARTS(
+            mantissa >= referenceMin && mantissa < referenceMin * 10,
+            "ripple::Number::toInternal()",
+            "Number is within reference range and has 'log' digits");
+    }
+
+    return {negative, mantissa, exponent};
+}
+
+template <class Rep>
+void
+Number::fromInternal(bool negative, Rep mantissa, int exponent)
+{
+    auto const sign = negative ? -1 : 1;
+
+    auto const& range = Number::range_.get();
+    auto const maxMantissa = range.max;
+
+    XRPL_ASSERT_PARTS(
+        mantissa <= maxMantissa,
+        "ripple::Number::fromInternal",
+        "mantissa in range");
+    if constexpr (std::is_signed_v<Rep>)
+        XRPL_ASSERT_PARTS(
+            mantissa >= -maxMantissa,
+            "xrpl::Number::fromInternal",
+            "negative mantissa in range");
+
+    mantissa_ = sign * static_cast<rep>(mantissa);
+    exponent_ = exponent;
+
+    XRPL_ASSERT_PARTS(
+        isnormal(), "ripple::Number::fromInternal", "Number is normalized");
+}
+
 constexpr Number
 Number::oneSmall()
 {
     return Number{
         false,
-        Number::smallRange.min,
+        Number::smallRange.referenceMin,
         -Number::smallRange.log,
         Number::unchecked{}};
 };
@@ -377,7 +430,7 @@ Number::oneLarge()
 {
     return Number{
         false,
-        Number::largeRange.min,
+        Number::largeRange.referenceMin,
         -Number::largeRange.log,
         Number::unchecked{}};
 };
@@ -394,97 +447,76 @@ Number::one()
 }
 
 // Use the member names in this static function for now so the diff is cleaner
-// TODO: Rename the function parameters to get rid of the "_" suffix
 template <class T>
 void
 doNormalize(
     bool& negative,
-    T& mantissa_,
-    int& exponent_,
+    T& mantissa,
+    int& exponent,
     MantissaRange::rep const& minMantissa,
     MantissaRange::rep const& maxMantissa)
 {
     auto constexpr minExponent = Number::minExponent;
     auto constexpr maxExponent = Number::maxExponent;
-    auto constexpr maxRep = Number::maxRep;
 
     using Guard = Number::Guard;
 
     constexpr Number zero = Number{};
-    if (mantissa_ == 0)
+    if (mantissa == 0 || (mantissa < minMantissa && exponent <= minExponent))
     {
-        mantissa_ = zero.mantissa_;
-        exponent_ = zero.exponent_;
-        negative = zero.negative_;
+        mantissa = zero.mantissa_;
+        exponent = zero.exponent_;
+        negative = false;
         return;
     }
-    auto m = mantissa_;
-    while ((m < minMantissa) && (exponent_ > minExponent))
+
+    auto m = mantissa;
+    while ((m < minMantissa) && (exponent > minExponent))
     {
         m *= 10;
-        --exponent_;
+        --exponent;
     }
     Guard g;
     if (negative)
         g.set_negative();
     while (m > maxMantissa)
     {
-        if (exponent_ >= maxExponent)
+        if (exponent >= maxExponent)
             throw std::overflow_error("Number::normalize 1");
         g.push(m % 10);
         m /= 10;
-        ++exponent_;
+        ++exponent;
     }
-    if ((exponent_ < minExponent) || (m < minMantissa))
+    if ((exponent < minExponent) || (m == 0))
     {
-        mantissa_ = zero.mantissa_;
-        exponent_ = zero.exponent_;
-        negative = zero.negative_;
+        mantissa = zero.mantissa_;
+        exponent = zero.exponent_;
+        negative = false;
         return;
     }
 
-    // When using the largeRange, "m" needs fit within an int64, even if
-    // the final mantissa_ is going to end up larger to fit within the
-    // MantissaRange. Cut it down here so that the rounding will be done while
-    // it's smaller.
-    //
-    // Example: 9,900,000,000,000,123,456 > 9,223,372,036,854,775,807,
-    //      so "m" will be modified to 990,000,000,000,012,345. Then that value
-    //      will be rounded to 990,000,000,000,012,345 or
-    //      990,000,000,000,012,346, depending on the rounding mode. Finally,
-    //      mantissa_ will be "m*10" so it fits within the range, and end up as
-    //      9,900,000,000,000,123,450 or 9,900,000,000,000,123,460.
-    // mantissa() will return mantissa_ / 10, and exponent() will return
-    // exponent_ + 1.
-    if (m > maxRep)
-    {
-        if (exponent_ >= maxExponent)
-            throw std::overflow_error("Number::normalize 1.5");
-        g.push(m % 10);
-        m /= 10;
-        ++exponent_;
-    }
-    // Before modification, m should be within the min/max range. After
-    // modification, it must be less than maxRep. In other words, the original
-    // value should have been no more than maxRep * 10.
-    // (maxRep * 10 > maxMantissa)
     XRPL_ASSERT_PARTS(
-        m <= maxRep,
+        m <= maxMantissa,
         "xrpl::doNormalize",
         "intermediate mantissa fits in int64");
-    mantissa_ = m;
+    mantissa = m;
 
     g.doRoundUp(
         negative,
-        mantissa_,
-        exponent_,
+        mantissa,
+        exponent,
         minMantissa,
         maxMantissa,
         "Number::normalize 2");
+
     XRPL_ASSERT_PARTS(
-        mantissa_ >= minMantissa && mantissa_ <= maxMantissa,
+        mantissa >= minMantissa && mantissa <= maxMantissa,
         "xrpl::doNormalize",
         "final mantissa fits in range");
+    XRPL_ASSERT_PARTS(
+        exponent >= minExponent && exponent <= maxExponent,
+        "xrpl::doNormalize",
+        "final exponent fits in range");
 }
 
 template <>
@@ -527,7 +559,13 @@ void
 Number::normalize()
 {
     auto const& range = range_.get();
-    normalize(negative_, mantissa_, exponent_, range.min, range.max);
+
+    auto [negative, mantissa, exponent] = toInternal();
+
+    normalize(negative, mantissa, exponent, range.min, range.max);
+    auto const sign = negative ? -1 : 1;
+
+    fromInternal(negative, mantissa, exponent);
 }
 
 // Copy the number, but set a new exponent. Because the mantissa doesn't change,
@@ -537,6 +575,9 @@ Number
 Number::shiftExponent(int exponentDelta) const
 {
     XRPL_ASSERT_PARTS(isnormal(), "xrpl::Number::shiftExponent", "normalized");
+
+    auto const [negative, mantissa, exponent] = toInternal();
+
     auto const newExponent = exponent_ + exponentDelta;
     if (newExponent >= maxExponent)
         throw std::overflow_error("Number::shiftExponent");
@@ -544,7 +585,9 @@ Number::shiftExponent(int exponentDelta) const
     {
         return Number{};
     }
-    Number const result{negative_, mantissa_, newExponent, unchecked{}};
+
+    Number const result{negative, mantissa, newExponent, unchecked{}};
+
     XRPL_ASSERT_PARTS(
         result.isnormal(),
         "xrpl::Number::shiftExponent",
@@ -578,13 +621,10 @@ Number::operator+=(Number const& y)
 
     // Need to use uint128_t, because large mantissas can overflow when added
     // together.
-    bool xn = negative_;
-    uint128_t xm = mantissa_;
-    auto xe = exponent_;
+    auto [xn, xm, xe] = toInternal<uint128_t>();
+
+    auto [yn, ym, ye] = y.toInternal<uint128_t>();
 
-    bool yn = y.negative_;
-    uint128_t ym = y.mantissa_;
-    auto ye = y.exponent_;
     Guard g;
     if (xe < ye)
     {
@@ -616,7 +656,7 @@ Number::operator+=(Number const& y)
     if (xn == yn)
     {
         xm += ym;
-        if (xm > maxMantissa || xm > maxRep)
+        if (xm > maxMantissa)
         {
             g.push(xm % 10);
             xm /= 10;
@@ -637,7 +677,7 @@ Number::operator+=(Number const& y)
             xe = ye;
             xn = yn;
         }
-        while (xm < minMantissa && xm * 10 <= maxRep)
+        while (xm < minMantissa)
         {
             xm *= 10;
             xm -= g.pop();
@@ -646,10 +686,8 @@ Number::operator+=(Number const& y)
         g.doRoundDown(xn, xm, xe, minMantissa);
     }
 
-    negative_ = xn;
-    mantissa_ = static_cast<internalrep>(xm);
-    exponent_ = xe;
-    normalize();
+    normalize(xn, xm, xe, minMantissa, maxMantissa);
+    fromInternal(xn, xm, xe);
     return *this;
 }
 
@@ -697,15 +735,11 @@ Number::operator*=(Number const& y)
     // *m = mantissa
     // *e = exponent
 
-    bool xn = negative_;
+    auto [xn, xm, xe] = toInternal();
     int xs = xn ? -1 : 1;
-    internalrep xm = mantissa_;
-    auto xe = exponent_;
 
-    bool yn = y.negative_;
+    auto [yn, ym, ye] = y.toInternal();
     int ys = yn ? -1 : 1;
-    internalrep ym = y.mantissa_;
-    auto ye = y.exponent_;
 
     auto zm = uint128_t(xm) * uint128_t(ym);
     auto ze = xe + ye;
@@ -719,7 +753,7 @@ Number::operator*=(Number const& y)
     auto const& minMantissa = range.min;
     auto const& maxMantissa = range.max;
 
-    while (zm > maxMantissa || zm > maxRep)
+    while (zm > maxMantissa)
     {
         // The following is optimization for:
         // g.push(static_cast<unsigned>(zm % 10));
@@ -736,11 +770,9 @@ Number::operator*=(Number const& y)
         minMantissa,
         maxMantissa,
         "Number::multiplication overflow : exponent is " + std::to_string(xe));
-    negative_ = zn;
-    mantissa_ = xm;
-    exponent_ = xe;
 
-    normalize();
+    normalize(zn, xm, xe, minMantissa, maxMantissa);
+    fromInternal(zn, xm, xe);
     return *this;
 }
 
@@ -759,15 +791,11 @@ Number::operator/=(Number const& y)
     // *m = mantissa
     // *e = exponent
 
-    bool np = negative_;
+    auto [np, nm, ne] = toInternal();
     int ns = (np ? -1 : 1);
-    auto nm = mantissa_;
-    auto ne = exponent_;
 
-    bool dp = y.negative_;
+    auto [dp, dm, de] = y.toInternal();
     int ds = (dp ? -1 : 1);
-    auto dm = y.mantissa_;
-    auto de = y.exponent_;
 
     auto const& range = range_.get();
     auto const& minMantissa = range.min;
@@ -833,9 +861,7 @@ Number::operator/=(Number const& y)
         }
     }
     normalize(zn, zm, ze, minMantissa, maxMantissa);
-    negative_ = zn;
-    mantissa_ = static_cast<internalrep>(zm);
-    exponent_ = ze;
+    fromInternal(zn, zm, ze);
     XRPL_ASSERT_PARTS(
         isnormal(), "xrpl::Number::operator/=", "result is normalized");
 
@@ -849,7 +875,7 @@ Number::operator rep() const
     Guard g;
     if (drops != 0)
     {
-        if (negative_)
+        if (drops < 0)
         {
             g.set_negative();
             drops = -drops;
@@ -861,7 +887,7 @@ Number::operator rep() const
         }
         for (; offset > 0; --offset)
         {
-            if (drops > maxRep / 10)
+            if (drops >= largeRange.min)
                 throw std::overflow_error("Number::operator rep() overflow");
             drops *= 10;
         }
@@ -896,9 +922,8 @@ to_string(Number const& amount)
     if (amount == zero)
         return "0";
 
-    auto exponent = amount.exponent_;
-    auto mantissa = amount.mantissa_;
-    bool const negative = amount.negative_;
+    // The mantissa must have a set number of decimal places for this to work
+    auto [negative, mantissa, exponent] = amount.toInternal();
 
     // Use scientific notation for exponents that are too small or too large
     auto const rangeLog = Number::mantissaLog();

src/test/basics/Number_test.cpp

@@ -51,9 +51,10 @@ public:
     test_limits()
     {
         auto const scale = Number::getMantissaScale();
-        testcase << "test_limits " << to_string(scale);
-        bool caught = false;
         auto const minMantissa = Number::minMantissa();
+
+        testcase << "test_limits " << to_string(scale) << ", " << minMantissa;
+        bool caught = false;
         try
         {
             Number x =
@@ -81,8 +82,9 @@ public:
             Number{},
             __LINE__);
         test(
+            // Use 1501 to force rounding up
             Number{false, minMantissa, 32000, Number::normalized{}} * 1'000 +
-                Number{false, 1'500, 32000, Number::normalized{}},
+                Number{false, 1'501, 32000, Number::normalized{}},
             Number{false, minMantissa + 2, 32003, Number::normalized{}},
             __LINE__);
         // 9,223,372,036,854,775,808
@@ -217,12 +219,12 @@ public:
                      9'999'999'999'999'999'990ULL,
                      -19,
                      Number::normalized{}}},
-                {Number{Number::maxRep},
+                {Number{Number::largestMantissa},
                  Number{6, -1},
-                 Number{Number::maxRep / 10, 1}},
-                {Number{Number::maxRep - 1},
+                 Number{Number::largestMantissa / 10, 1}},
+                {Number{Number::largestMantissa - 1},
                  Number{1, 0},
-                 Number{Number::maxRep}},
+                 Number{Number::largestMantissa}},
                 // Test extremes
                 {
                     // Each Number operand rounds up, so the actual mantissa is
@@ -240,11 +242,11 @@ public:
                     Number{2, 19},
                 },
                 {
-                    // Does not round. Mantissas are going to be > maxRep, so if
-                    // added together as uint64_t's, the result will overflow.
-                    // With addition using uint128_t, there's no problem. After
-                    // normalizing, the resulting mantissa ends up less than
-                    // maxRep.
+                    // Does not round. Mantissas are going to be >
+                    // largestMantissa, so if added together as uint64_t's, the
+                    // result will overflow. With addition using uint128_t,
+                    // there's no problem. After normalizing, the resulting
+                    // mantissa ends up less than largestMantissa.
                     Number{
                         false,
                         9'999'999'999'999'999'990ULL,
@@ -371,16 +373,24 @@ public:
                 {Number{1'000'000'000'000'000'001, -18},
                  Number{1'000'000'000'000'000'000, -18},
                  Number{1'000'000'000'000'000'000, -36}},
-                {Number{Number::maxRep},
+                {Number{Number::largestMantissa},
                  Number{6, -1},
-                 Number{Number::maxRep - 1}},
-                {Number{false, Number::maxRep + 1, 0, Number::normalized{}},
+                 Number{Number::largestMantissa - 1}},
+                {Number{
+                     false,
+                     Number::largestMantissa + 1,
+                     0,
+                     Number::normalized{}},
                  Number{1, 0},
-                 Number{Number::maxRep / 10 + 1, 1}},
-                {Number{false, Number::maxRep + 1, 0, Number::normalized{}},
+                 Number{Number::largestMantissa / 10 + 1, 1}},
+                {Number{
+                     false,
+                     Number::largestMantissa + 1,
+                     0,
+                     Number::normalized{}},
                  Number{3, 0},
-                 Number{Number::maxRep}},
-                {power(2, 63), Number{3, 0}, Number{Number::maxRep}},
+                 Number{Number::largestMantissa}},
+                {power(2, 63), Number{3, 0}, Number{Number::largestMantissa}},
             });
         auto test = [this](auto const& c) {
             for (auto const& [x, y, z] : c)
@@ -403,14 +413,16 @@ public:
         auto const scale = Number::getMantissaScale();
         testcase << "test_mul " << to_string(scale);
 
-        using Case = std::tuple<Number, Number, Number>;
+        // Case: Factor 1, Factor 2, Expected product, Line number
+        using Case = std::tuple<Number, Number, Number, int>;
         auto test = [this](auto const& c) {
-            for (auto const& [x, y, z] : c)
+            for (auto const& [x, y, z, line] : c)
             {
                 auto const result = x * y;
                 std::stringstream ss;
                 ss << x << " * " << y << " = " << result << ". Expected: " << z;
-                BEAST_EXPECTS(result == z, ss.str());
+                BEAST_EXPECTS(
+                    result == z, ss.str() + " line: " + std::to_string(line));
             }
         };
         auto tests = [&](auto const& cSmall, auto const& cLarge) {
@@ -420,78 +432,105 @@ public:
                 test(cLarge);
         };
         auto const maxMantissa = Number::maxMantissa();
+        auto const maxInternalMantissa =
+            static_cast<std::uint64_t>(
+                static_cast<std::int64_t>(power(10, Number::mantissaLog()))) *
+                10 -
+            1;
 
         saveNumberRoundMode save{Number::setround(Number::to_nearest)};
         {
             auto const cSmall = std::to_array<Case>({
-                {Number{7}, Number{8}, Number{56}},
+                {Number{7}, Number{8}, Number{56}, __LINE__},
                 {Number{1414213562373095, -15},
                  Number{1414213562373095, -15},
-                 Number{2000000000000000, -15}},
+                 Number{2000000000000000, -15},
+                 __LINE__},
                 {Number{-1414213562373095, -15},
                  Number{1414213562373095, -15},
-                 Number{-2000000000000000, -15}},
+                 Number{-2000000000000000, -15},
+                 __LINE__},
                 {Number{-1414213562373095, -15},
                  Number{-1414213562373095, -15},
-                 Number{2000000000000000, -15}},
+                 Number{2000000000000000, -15},
+                 __LINE__},
                 {Number{3214285714285706, -15},
                  Number{3111111111111119, -15},
-                 Number{1000000000000000, -14}},
+                 Number{1000000000000000, -14},
+                 __LINE__},
                 {Number{1000000000000000, -32768},
                  Number{1000000000000000, -32768},
-                 Number{0}},
+                 Number{0},
+                 __LINE__},
                 // Maximum mantissa range
                 {Number{9'999'999'999'999'999, 0},
                  Number{9'999'999'999'999'999, 0},
-                 Number{9'999'999'999'999'998, 16}},
+                 Number{9'999'999'999'999'998, 16},
+                 __LINE__},
             });
             auto const cLarge = std::to_array<Case>({
                 // Note that items with extremely large mantissas need to be
                 // calculated, because otherwise they overflow uint64. Items
                 // from C with larger mantissa
-                {Number{7}, Number{8}, Number{56}},
+                {Number{7}, Number{8}, Number{56}, __LINE__},
                 {Number{1414213562373095, -15},
                  Number{1414213562373095, -15},
-                 Number{1999999999999999862, -18}},
+                 Number{1999999999999999862, -18},
+                 __LINE__},
                 {Number{-1414213562373095, -15},
                  Number{1414213562373095, -15},
-                 Number{-1999999999999999862, -18}},
+                 Number{-1999999999999999862, -18},
+                 __LINE__},
                 {Number{-1414213562373095, -15},
                  Number{-1414213562373095, -15},
-                 Number{1999999999999999862, -18}},
+                 Number{1999999999999999862, -18},
+                 __LINE__},
                 {Number{3214285714285706, -15},
                  Number{3111111111111119, -15},
                  Number{
                      false,
                      9'999'999'999'999'999'579ULL,
                      -18,
-                     Number::normalized{}}},
+                     Number::normalized{}},
+                 __LINE__},
                 {Number{1000000000000000000, -32768},
                  Number{1000000000000000000, -32768},
-                 Number{0}},
+                 Number{0},
+                 __LINE__},
                 // Items from cSmall expanded for the larger mantissa,
                 // except duplicates. Sadly, it looks like sqrt(2)^2 != 2
                 // with higher precision
                 {Number{1414213562373095049, -18},
                  Number{1414213562373095049, -18},
-                 Number{2000000000000000001, -18}},
+                 Number{2000000000000000001, -18},
+                 __LINE__},
                 {Number{-1414213562373095048, -18},
                  Number{1414213562373095048, -18},
-                 Number{-1999999999999999998, -18}},
+                 Number{-1999999999999999998, -18},
+                 __LINE__},
                 {Number{-1414213562373095048, -18},
                  Number{-1414213562373095049, -18},
-                 Number{1999999999999999999, -18}},
+                 Number{1999999999999999999, -18},
+                 __LINE__},
                 {Number{3214285714285714278, -18},
                  Number{3111111111111111119, -18},
-                 Number{10, 0}},
-                // Maximum mantissa range - rounds up to 1e19
+                 Number{10, 0},
+                 __LINE__},
+                // Maximum internal mantissa range - rounds up to 1e19
+                {Number{false, maxInternalMantissa, 0, Number::normalized{}},
+                 Number{false, maxInternalMantissa, 0, Number::normalized{}},
+                 Number{1, 38},
+                 __LINE__},
+                // Maximum actual mantissa range - same as int64 range
                 {Number{false, maxMantissa, 0, Number::normalized{}},
                  Number{false, maxMantissa, 0, Number::normalized{}},
-                 Number{1, 38}},
+                 Number{85'070'591'730'234'615'85, 19},
+                 __LINE__},
                 // Maximum int64 range
-                {Number{Number::maxRep, 0},
-                 Number{Number::maxRep, 0},
-                 Number{85'070'591'730'234'615'85, 19}},
+                {Number{Number::largestMantissa, 0},
+                 Number{Number::largestMantissa, 0},
+                 Number{85'070'591'730'234'615'85, 19},
+                 __LINE__},
             });
             tests(cSmall, cLarge);
         }
@@ -500,76 +539,101 @@ public:
                  << " towards_zero";
         {
             auto const cSmall = std::to_array<Case>(
-                {{Number{7}, Number{8}, Number{56}},
+                {{Number{7}, Number{8}, Number{56}, __LINE__},
                  {Number{1414213562373095, -15},
                   Number{1414213562373095, -15},
-                  Number{1999999999999999, -15}},
+                  Number{1999999999999999, -15},
+                  __LINE__},
                  {Number{-1414213562373095, -15},
                   Number{1414213562373095, -15},
-                  Number{-1999999999999999, -15}},
+                  Number{-1999999999999999, -15},
+                  __LINE__},
                  {Number{-1414213562373095, -15},
                   Number{-1414213562373095, -15},
-                  Number{1999999999999999, -15}},
+                  Number{1999999999999999, -15},
+                  __LINE__},
                  {Number{3214285714285706, -15},
                   Number{3111111111111119, -15},
-                  Number{9999999999999999, -15}},
+                  Number{9999999999999999, -15},
+                  __LINE__},
                  {Number{1000000000000000, -32768},
                   Number{1000000000000000, -32768},
-                  Number{0}}});
+                  Number{0},
+                  __LINE__}});
             auto const cLarge = std::to_array<Case>(
                 // Note that items with extremely large mantissas need to be
                 // calculated, because otherwise they overflow uint64. Items
                 // from C with larger mantissa
                 {
-                    {Number{7}, Number{8}, Number{56}},
+                    {Number{7}, Number{8}, Number{56}, __LINE__},
                     {Number{1414213562373095, -15},
                      Number{1414213562373095, -15},
-                     Number{1999999999999999861, -18}},
+                     Number{1999999999999999861, -18},
+                     __LINE__},
                     {Number{-1414213562373095, -15},
                      Number{1414213562373095, -15},
-                     Number{-1999999999999999861, -18}},
+                     Number{-1999999999999999861, -18},
+                     __LINE__},
                     {Number{-1414213562373095, -15},
                      Number{-1414213562373095, -15},
-                     Number{1999999999999999861, -18}},
+                     Number{1999999999999999861, -18},
+                     __LINE__},
                     {Number{3214285714285706, -15},
                      Number{3111111111111119, -15},
                      Number{
                          false,
                          9999999999999999579ULL,
                          -18,
-                         Number::normalized{}}},
+                         Number::normalized{}},
+                     __LINE__},
                     {Number{1000000000000000000, -32768},
                      Number{1000000000000000000, -32768},
-                     Number{0}},
+                     Number{0},
+                     __LINE__},
                     // Items from cSmall expanded for the larger mantissa,
                     // except duplicates. Sadly, it looks like sqrt(2)^2 != 2
                     // with higher precision
                     {Number{1414213562373095049, -18},
                      Number{1414213562373095049, -18},
-                     Number{2, 0}},
+                     Number{2, 0},
+                     __LINE__},
                     {Number{-1414213562373095048, -18},
                      Number{1414213562373095048, -18},
-                     Number{-1999999999999999997, -18}},
+                     Number{-1999999999999999997, -18},
+                     __LINE__},
                     {Number{-1414213562373095048, -18},
                      Number{-1414213562373095049, -18},
-                     Number{1999999999999999999, -18}},
+                     Number{1999999999999999999, -18},
+                     __LINE__},
                     {Number{3214285714285714278, -18},
                      Number{3111111111111111119, -18},
-                     Number{10, 0}},
-                    // Maximum mantissa range - rounds down to maxMantissa/10e1
+                     Number{10, 0},
+                     __LINE__},
+                    // Maximum internal mantissa range - rounds down to
+                    // maxMantissa/10e1
+                    // 99'999'999'999'999'999'800'000'000'000'000'000'100
+                    {Number{
+                         false, maxInternalMantissa, 0, Number::normalized{}},
+                     Number{
+                         false, maxInternalMantissa, 0, Number::normalized{}},
+                     Number{
+                         false,
+                         maxInternalMantissa / 10 - 1,
+                         20,
+                         Number::normalized{}},
+                     __LINE__},
+                    // Maximum actual mantissa range - same as int64
                     // 99'999'999'999'999'999'800'000'000'000'000'000'100
                     {Number{false, maxMantissa, 0, Number::normalized{}},
                      Number{false, maxMantissa, 0, Number::normalized{}},
-                     Number{
-                         false,
-                         maxMantissa / 10 - 1,
-                         20,
-                         Number::normalized{}}},
+                     Number{85'070'591'730'234'615'84, 19},
+                     __LINE__},
                     // Maximum int64 range
                     // 85'070'591'730'234'615'847'396'907'784'232'501'249
-                    {Number{Number::maxRep, 0},
-                     Number{Number::maxRep, 0},
-                     Number{85'070'591'730'234'615'84, 19}},
+                    {Number{Number::largestMantissa, 0},
+                     Number{Number::largestMantissa, 0},
+                     Number{85'070'591'730'234'615'84, 19},
+                     __LINE__},
                 });
             tests(cSmall, cLarge);
         }
@@ -578,76 +642,100 @@ public:
                  << " downward";
         {
             auto const cSmall = std::to_array<Case>(
-                {{Number{7}, Number{8}, Number{56}},
+                {{Number{7}, Number{8}, Number{56}, __LINE__},
                  {Number{1414213562373095, -15},
                   Number{1414213562373095, -15},
-                  Number{1999999999999999, -15}},
+                  Number{1999999999999999, -15},
+                  __LINE__},
                  {Number{-1414213562373095, -15},
                   Number{1414213562373095, -15},
-                  Number{-2000000000000000, -15}},
+                  Number{-2000000000000000, -15},
+                  __LINE__},
                  {Number{-1414213562373095, -15},
                   Number{-1414213562373095, -15},
-                  Number{1999999999999999, -15}},
+                  Number{1999999999999999, -15},
+                  __LINE__},
                  {Number{3214285714285706, -15},
                   Number{3111111111111119, -15},
-                  Number{9999999999999999, -15}},
+                  Number{9999999999999999, -15},
+                  __LINE__},
                  {Number{1000000000000000, -32768},
                   Number{1000000000000000, -32768},
-                  Number{0}}});
+                  Number{0},
+                  __LINE__}});
             auto const cLarge = std::to_array<Case>(
                 // Note that items with extremely large mantissas need to be
                 // calculated, because otherwise they overflow uint64. Items
                 // from C with larger mantissa
                 {
-                    {Number{7}, Number{8}, Number{56}},
+                    {Number{7}, Number{8}, Number{56}, __LINE__},
                     {Number{1414213562373095, -15},
                      Number{1414213562373095, -15},
-                     Number{1999999999999999861, -18}},
+                     Number{1999999999999999861, -18},
+                     __LINE__},
                     {Number{-1414213562373095, -15},
                      Number{1414213562373095, -15},
-                     Number{-1999999999999999862, -18}},
+                     Number{-1999999999999999862, -18},
+                     __LINE__},
                     {Number{-1414213562373095, -15},
                      Number{-1414213562373095, -15},
-                     Number{1999999999999999861, -18}},
+                     Number{1999999999999999861, -18},
+                     __LINE__},
                     {Number{3214285714285706, -15},
                      Number{3111111111111119, -15},
                      Number{
                          false,
                          9'999'999'999'999'999'579ULL,
                          -18,
-                         Number::normalized{}}},
+                         Number::normalized{}},
+                     __LINE__},
                     {Number{1000000000000000000, -32768},
                      Number{1000000000000000000, -32768},
-                     Number{0}},
+                     Number{0},
+                     __LINE__},
                     // Items from cSmall expanded for the larger mantissa,
                     // except duplicates. Sadly, it looks like sqrt(2)^2 != 2
                     // with higher precision
                     {Number{1414213562373095049, -18},
                      Number{1414213562373095049, -18},
-                     Number{2, 0}},
+                     Number{2, 0},
+                     __LINE__},
                     {Number{-1414213562373095048, -18},
                      Number{1414213562373095048, -18},
-                     Number{-1999999999999999998, -18}},
+                     Number{-1999999999999999998, -18},
+                     __LINE__},
                     {Number{-1414213562373095048, -18},
                      Number{-1414213562373095049, -18},
-                     Number{1999999999999999999, -18}},
+                     Number{1999999999999999999, -18},
+                     __LINE__},
                     {Number{3214285714285714278, -18},
                      Number{3111111111111111119, -18},
-                     Number{10, 0}},
-                    // Maximum mantissa range - rounds down to maxMantissa/10e1
+                     Number{10, 0},
+                     __LINE__},
+                    // Maximum internal mantissa range - rounds down to
+                    // maxMantissa/10-1
                     // 99'999'999'999'999'999'800'000'000'000'000'000'100
-                    {Number{false, maxMantissa, 0, Number::normalized{}},
-                     Number{false, maxMantissa, 0, Number::normalized{}},
+                    {Number{
+                         false, maxInternalMantissa, 0, Number::normalized{}},
+                     Number{
+                         false, maxInternalMantissa, 0, Number::normalized{}},
                      Number{
                          false,
-                         maxMantissa / 10 - 1,
+                         maxInternalMantissa / 10 - 1,
                          20,
-                         Number::normalized{}}},
+                         Number::normalized{}},
+                     __LINE__},
+                    // Maximum mantissa range - same as int64
+                    {Number{false, maxMantissa, 0, Number::normalized{}},
+                     Number{false, maxMantissa, 0, Number::normalized{}},
+                     Number{85'070'591'730'234'615'84, 19},
+                     __LINE__},
                     // Maximum int64 range
                     // 85'070'591'730'234'615'847'396'907'784'232'501'249
-                    {Number{Number::maxRep, 0},
-                     Number{Number::maxRep, 0},
-                     Number{85'070'591'730'234'615'84, 19}},
+                    {Number{Number::largestMantissa, 0},
+                     Number{Number::largestMantissa, 0},
+                     Number{85'070'591'730'234'615'84, 19},
+                     __LINE__},
                 });
             tests(cSmall, cLarge);
         }
@@ -656,68 +744,91 @@ public:
                  << " upward";
         {
             auto const cSmall = std::to_array<Case>(
-                {{Number{7}, Number{8}, Number{56}},
+                {{Number{7}, Number{8}, Number{56}, __LINE__},
                  {Number{1414213562373095, -15},
                   Number{1414213562373095, -15},
-                  Number{2000000000000000, -15}},
+                  Number{2000000000000000, -15},
+                  __LINE__},
                  {Number{-1414213562373095, -15},
                   Number{1414213562373095, -15},
-                  Number{-1999999999999999, -15}},
+                  Number{-1999999999999999, -15},
+                  __LINE__},
                  {Number{-1414213562373095, -15},
                   Number{-1414213562373095, -15},
-                  Number{2000000000000000, -15}},
+                  Number{2000000000000000, -15},
+                  __LINE__},
                  {Number{3214285714285706, -15},
                   Number{3111111111111119, -15},
-                  Number{1000000000000000, -14}},
+                  Number{1000000000000000, -14},
+                  __LINE__},
                  {Number{1000000000000000, -32768},
                   Number{1000000000000000, -32768},
-                  Number{0}}});
+                  Number{0},
+                  __LINE__}});
             auto const cLarge = std::to_array<Case>(
                 // Note that items with extremely large mantissas need to be
                 // calculated, because otherwise they overflow uint64. Items
                 // from C with larger mantissa
                 {
-                    {Number{7}, Number{8}, Number{56}},
+                    {Number{7}, Number{8}, Number{56}, __LINE__},
                     {Number{1414213562373095, -15},
                      Number{1414213562373095, -15},
-                     Number{1999999999999999862, -18}},
+                     Number{1999999999999999862, -18},
+                     __LINE__},
                     {Number{-1414213562373095, -15},
                      Number{1414213562373095, -15},
-                     Number{-1999999999999999861, -18}},
+                     Number{-1999999999999999861, -18},
+                     __LINE__},
                     {Number{-1414213562373095, -15},
                      Number{-1414213562373095, -15},
-                     Number{1999999999999999862, -18}},
+                     Number{1999999999999999862, -18},
+                     __LINE__},
                     {Number{3214285714285706, -15},
                      Number{3111111111111119, -15},
-                     Number{999999999999999958, -17}},
+                     Number{999999999999999958, -17},
+                     __LINE__},
                     {Number{1000000000000000000, -32768},
                      Number{1000000000000000000, -32768},
-                     Number{0}},
+                     Number{0},
+                     __LINE__},
                     // Items from cSmall expanded for the larger mantissa,
                     // except duplicates. Sadly, it looks like sqrt(2)^2 != 2
                     // with higher precision
                     {Number{1414213562373095049, -18},
                      Number{1414213562373095049, -18},
-                     Number{2000000000000000001, -18}},
+                     Number{2000000000000000001, -18},
+                     __LINE__},
                     {Number{-1414213562373095048, -18},
                      Number{1414213562373095048, -18},
-                     Number{-1999999999999999997, -18}},
+                     Number{-1999999999999999997, -18},
+                     __LINE__},
                     {Number{-1414213562373095048, -18},
                      Number{-1414213562373095049, -18},
-                     Number{2, 0}},
+                     Number{2, 0},
+                     __LINE__},
                     {Number{3214285714285714278, -18},
                      Number{3111111111111111119, -18},
-                     Number{1000000000000000001, -17}},
-                    // Maximum mantissa range - rounds up to minMantissa*10
-                    // 1e19*1e19=1e38
+                     Number{1000000000000000001, -17},
+                     __LINE__},
+                    // Maximum internal mantissa range - rounds up to
+                    // minMantissa*10 1e19*1e19=1e38
+                    {Number{
+                         false, maxInternalMantissa, 0, Number::normalized{}},
+                     Number{
+                         false, maxInternalMantissa, 0, Number::normalized{}},
+                     Number{1, 38},
+                     __LINE__},
+                    // Maximum mantissa range - same as int64
                     {Number{false, maxMantissa, 0, Number::normalized{}},
                      Number{false, maxMantissa, 0, Number::normalized{}},
-                     Number{1, 38}},
+                     Number{85'070'591'730'234'615'85, 19},
+                     __LINE__},
                     // Maximum int64 range
                     // 85'070'591'730'234'615'847'396'907'784'232'501'249
-                    {Number{Number::maxRep, 0},
-                     Number{Number::maxRep, 0},
-                     Number{85'070'591'730'234'615'85, 19}},
+                    {Number{Number::largestMantissa, 0},
+                     Number{Number::largestMantissa, 0},
+                     Number{85'070'591'730'234'615'85, 19},
+                     __LINE__},
                 });
             tests(cSmall, cLarge);
         }
@@ -990,6 +1101,13 @@ public:
         };
         */
 
+        auto const maxMantissa = Number::maxMantissa();
+        auto const maxInternalMantissa =
+            static_cast<std::uint64_t>(
+                static_cast<std::int64_t>(power(10, Number::mantissaLog()))) *
+                10 -
+            1;
+
         auto const cSmall = std::to_array<Case>(
             {{Number{2}, 2, Number{1414213562373095049, -18}},
              {Number{2'000'000}, 2, Number{1414213562373095049, -15}},
@@ -1001,17 +1119,17 @@ public:
              {Number{0}, 5, Number{0}},
              {Number{5625, -4}, 2, Number{75, -2}}});
         auto const cLarge = std::to_array<Case>({
-            {Number{false, Number::maxMantissa() - 9, -1, Number::normalized{}},
+            {Number{false, maxInternalMantissa - 9, -1, Number::normalized{}},
              2,
              Number{false, 999'999'999'999'999'999, -9, Number::normalized{}}},
-            {Number{false, Number::maxMantissa() - 9, 0, Number::normalized{}},
+            {Number{false, maxInternalMantissa - 9, 0, Number::normalized{}},
              2,
              Number{
                  false, 3'162'277'660'168'379'330, -9, Number::normalized{}}},
-            {Number{Number::maxRep},
+            {Number{Number::largestMantissa},
              2,
              Number{false, 3'037'000'499'976049692, -9, Number::normalized{}}},
-            {Number{Number::maxRep},
+            {Number{Number::largestMantissa},
              4,
              Number{false, 55'108'98747006743627, -14, Number::normalized{}}},
         });
@@ -1070,7 +1188,7 @@ public:
             Number{5, -1},
             Number{0},
             Number{5625, -4},
-            Number{Number::maxRep},
+            Number{Number::largestMantissa},
         });
         test(cSmall);
         bool caught = false;
@@ -1436,20 +1554,20 @@ public:
             case MantissaRange::large:
                 // Test the edges
                 // ((exponent < -(28)) || (exponent > -(8)))))
-                test(Number::min(), "1e-32750");
+                test(Number::min(), "922337203685477581e-32768");
                 test(Number::max(), "9223372036854775807e32768");
                 test(Number::lowest(), "-9223372036854775807e32768");
                 {
                     NumberRoundModeGuard mg(Number::towards_zero);
 
                     auto const maxMantissa = Number::maxMantissa();
-                    BEAST_EXPECT(maxMantissa == 9'999'999'999'999'999'999ULL);
+                    BEAST_EXPECT(maxMantissa == 9'223'372'036'854'775'807ULL);
                     test(
                         Number{false, maxMantissa, 0, Number::normalized{}},
-                        "9999999999999999990");
+                        "9223372036854775807");
                     test(
                         Number{true, maxMantissa, 0, Number::normalized{}},
-                        "-9999999999999999990");
+                        "-9223372036854775807");
 
                     test(
                         Number{std::numeric_limits<std::int64_t>::max(), 0},
@@ -1690,7 +1808,7 @@ public:
             Number const initalXrp{INITIAL_XRP};
             BEAST_EXPECT(initalXrp.exponent() > 0);
 
-            Number const maxInt64{Number::maxRep};
+            Number const maxInt64{Number::largestMantissa};
             BEAST_EXPECT(maxInt64.exponent() > 0);
             // 85'070'591'730'234'615'865'843'651'857'942'052'864 - 38 digits
             BEAST_EXPECT(
@@ -1710,7 +1828,7 @@ public:
             Number const initalXrp{INITIAL_XRP};
             BEAST_EXPECT(initalXrp.exponent() <= 0);
 
-            Number const maxInt64{Number::maxRep};
+            Number const maxInt64{Number::largestMantissa};
             BEAST_EXPECT(maxInt64.exponent() <= 0);
             // 85'070'591'730'234'615'847'396'907'784'232'501'249 - 38 digits
             BEAST_EXPECT(
@@ -1718,16 +1836,47 @@ public:
 
             NumberRoundModeGuard mg(Number::towards_zero);
 
-            auto const maxMantissa = Number::maxMantissa();
-            Number const max =
-                Number{false, maxMantissa, 0, Number::normalized{}};
-            BEAST_EXPECT(max.mantissa() == maxMantissa / 10);
-            BEAST_EXPECT(max.exponent() == 1);
-            // 99'999'999'999'999'999'800'000'000'000'000'000'100 - also 38
-            // digits
-            BEAST_EXPECT((
-                power(max, 2) ==
-                Number{false, maxMantissa / 10 - 1, 20, Number::normalized{}}));
+            {
+                auto const maxInternalMantissa =
+                    static_cast<std::uint64_t>(static_cast<std::int64_t>(
+                        power(10, Number::mantissaLog()))) *
+                        10 -
+                    1;
+
+                // Rounds down to fit under 2^63
+                Number const max =
+                    Number{false, maxInternalMantissa, 0, Number::normalized{}};
+                // No alterations by the accessors
+                BEAST_EXPECT(max.mantissa() == maxInternalMantissa / 10);
+                BEAST_EXPECT(max.exponent() == 1);
+                // 99'999'999'999'999'999'800'000'000'000'000'000'100 - also 38
+                // digits
+                BEAST_EXPECT(
+                    (power(max, 2) ==
+                     Number{
+                         false,
+                         maxInternalMantissa / 10 - 1,
+                         20,
+                         Number::normalized{}}));
+            }
+
+            {
+                auto const maxMantissa = Number::maxMantissa();
+                Number const max =
+                    Number{false, maxMantissa, 0, Number::normalized{}};
+                // No alterations by the accessors
+                BEAST_EXPECT(max.mantissa() == maxMantissa);
+                BEAST_EXPECT(max.exponent() == 0);
+                // 85'070'591'730'234'615'847'396'907'784'232'501'249 - also 38
+                // digits
+                BEAST_EXPECT(
+                    (power(max, 2) ==
+                     Number{
+                         false,
+                         85'070'591'730'234'615'84,
+                         19,
+                         Number::normalized{}}));
+            }
         }
     }