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authorRichard Linden <none@none>2012-11-08 23:42:18 -0800
committerRichard Linden <none@none>2012-11-08 23:42:18 -0800
commit0bb0bd514b235948c1a21c81ab0e8ab6223b1990 (patch)
treee0d49acc9074d0a5ed30c9c53fde908e5305b10f /indra/llcommon/llunit.h
parented17c181dd37f56b808838748d289ee7bb5567ec (diff)
SH-3499 WIP Ensure asset stats output is correct
Finished making LLUnit implicitly convertible to/from scalar integer values cleaned up test code
Diffstat (limited to 'indra/llcommon/llunit.h')
-rw-r--r--indra/llcommon/llunit.h404
1 files changed, 183 insertions, 221 deletions
diff --git a/indra/llcommon/llunit.h b/indra/llcommon/llunit.h
index 4519905707..0dcafbe26e 100644
--- a/indra/llcommon/llunit.h
+++ b/indra/llcommon/llunit.h
@@ -30,326 +30,288 @@
#include "stdtypes.h"
#include "llpreprocessor.h"
-template<typename STORAGE_TYPE, typename BASE_UNIT, typename DERIVED_UNIT = BASE_UNIT>
-struct LLUnitType : public BASE_UNIT
+namespace LLUnits
{
- typedef DERIVED_UNIT unit_t;
-
- typedef typename STORAGE_TYPE storage_t;
- typedef void is_unit_tag_t;
-
- LLUnitType()
- {}
-
- LLUnitType(storage_t value)
- : BASE_UNIT(convertToBase(value))
- {}
-
- // implicit downcast
- operator unit_t& ()
- {
- return static_cast<unit_t&>(*this);
- }
-
- operator storage_t () const
- {
- return value();
- }
-
- storage_t value() const
- {
- return convertToDerived(mBaseValue);
- }
-
- template<typename CONVERTED_TYPE>
- storage_t as() const
- {
- return CONVERTED_TYPE(*this).value();
- }
-
-protected:
- static storage_t convertToBase(storage_t derived_value)
- {
- return (storage_t)((F32)derived_value * unit_t::conversionToBaseFactor());
- }
-
- static storage_t convertToDerived(storage_t base_value)
+template<typename DERIVED_UNITS_TAG, typename BASE_UNITS_TAG>
+struct ConversionFactor
+{
+ static F64 get()
{
- return (storage_t)((F32)base_value / unit_t::conversionToBaseFactor());
+ llstatic_assert(sizeof(DERIVED_UNITS_TAG) == 0, "Cannot convert between types.");
}
+};
+template<typename BASE_UNITS_TAG>
+struct ConversionFactor<BASE_UNITS_TAG, BASE_UNITS_TAG>
+{
+ static F64 get() { return 1.0; }
};
+}
-template<typename STORAGE_TYPE, typename T>
-struct LLUnitType<STORAGE_TYPE, T, T>
+template<typename UNIT_TYPE, typename STORAGE_TYPE>
+struct LLUnit
{
- typedef T unit_t;
- typedef STORAGE_TYPE storage_t;
+ typedef LLUnit<UNIT_TYPE, STORAGE_TYPE> self_t;
+ typedef typename STORAGE_TYPE storage_t;
typedef void is_unit_tag_t;
- LLUnitType()
- : mBaseValue()
+ LLUnit(storage_t value = storage_t())
+ : mValue(value)
{}
- LLUnitType(storage_t value)
- : mBaseValue(value)
+ template<typename OTHER_UNIT, typename OTHER_STORAGE>
+ LLUnit(LLUnit<OTHER_UNIT, OTHER_STORAGE> other)
+ : mValue(convert(other))
{}
- unit_t& operator=(storage_t value)
+ LLUnit(self_t& other)
+ : mValue(other.mValue)
+ {}
+
+ self_t& operator = (storage_t value)
{
- setBaseValue(value);
+ mValue = value;
return *this;
}
- //implicit downcast
- operator unit_t& ()
+ template<typename OTHER_UNIT, typename OTHER_STORAGE>
+ self_t& operator = (LLUnit<OTHER_UNIT, OTHER_STORAGE> other)
{
- return static_cast<unit_t&>(*this);
+ mValue = convert(other);
+ return *this;
}
- operator storage_t () const
+ operator storage_t() const
{
return value();
}
- storage_t value() const { return mBaseValue; }
-
- template<typename CONVERTED_TYPE>
- storage_t as() const
+ storage_t value() const
{
- return CONVERTED_TYPE(*this).value();
+ return mValue;
}
- static storage_t convertToBase(storage_t derived_value)
+ void operator += (storage_t value)
{
- return (storage_t)derived_value;
+ mValue += value;
}
- static storage_t convertToDerived(storage_t base_value)
+ template<typename OTHER_UNIT, typename OTHER_STORAGE>
+ void operator += (LLUnit<OTHER_UNIT, OTHER_STORAGE> other)
{
- return (storage_t)base_value;
+ mValue += convert(other);
}
- void operator += (const unit_t other)
+ void operator -= (storage_t value)
{
- mBaseValue += other.mBaseValue;
+ mValue -= value;
}
- void operator -= (const unit_t other)
+ template<typename OTHER_UNIT, typename OTHER_STORAGE>
+ void operator -= (LLUnit<OTHER_UNIT, OTHER_STORAGE> other)
{
- mBaseValue -= other.mBaseValue;
+ mValue -= convert(other);
}
void operator *= (storage_t multiplicand)
{
- mBaseValue *= multiplicand;
+ mValue *= multiplicand;
+ }
+
+ template<typename OTHER_UNIT, typename OTHER_STORAGE>
+ void operator *= (LLUnit<OTHER_UNIT, OTHER_STORAGE> multiplicand)
+ {
+ llstatic_assert(sizeof(OTHER_UNIT) == false, "Multiplication of unit types not supported.");
}
void operator /= (storage_t divisor)
{
- mBaseValue /= divisor;
+ mValue /= divisor;
}
-protected:
- void setBaseValue(storage_t value)
+ template<typename OTHER_UNIT, typename OTHER_STORAGE>
+ void operator /= (LLUnit<OTHER_UNIT, OTHER_STORAGE> divisor)
{
- mBaseValue = value;
+ llstatic_assert(sizeof(OTHER_UNIT) == false, "Division of unit types not supported.");
}
- storage_t mBaseValue;
-};
+ template<typename SOURCE_UNITS, typename SOURCE_VALUE>
+ static storage_t convert(LLUnit<SOURCE_UNITS, SOURCE_VALUE> v)
+ {
+ return (storage_t)(v.value()
+ * LLUnits::ConversionFactor<SOURCE_UNITS, typename UNIT_TYPE::base_unit_t>::get()
+ * LLUnits::ConversionFactor<typename UNIT_TYPE::base_unit_t, UNIT_TYPE>::get());
+ }
-template<typename STORAGE_TYPE, typename BASE_UNIT, typename DERIVED_UNIT>
-struct LLUnitTypeWrapper
-: public LLUnitType<STORAGE_TYPE, BASE_UNIT, DERIVED_UNIT>
-{
- typedef LLUnitType<STORAGE_TYPE, BASE_UNIT, DERIVED_UNIT> unit_t;
- LLUnitTypeWrapper(const unit_t& other)
- : unit_t(other)
- {}
-};
+protected:
+ storage_t mValue;
+};
//
// operator +
//
-template<typename STORAGE_TYPE, typename BASE_UNIT, typename DERIVED_UNIT, typename STORAGE_TYPE2, typename BASE_UNIT2, typename DERIVED_UNIT2>
-DERIVED_UNIT operator + (typename LLUnitType<STORAGE_TYPE, BASE_UNIT, DERIVED_UNIT>::storage_t first, LLUnitType<STORAGE_TYPE2, BASE_UNIT2, DERIVED_UNIT2> second)
+template<typename STORAGE_TYPE1, typename UNIT_TYPE1, typename STORAGE_TYPE2, typename UNIT_TYPE2>
+LLUnit<STORAGE_TYPE1, UNIT_TYPE1> operator + (LLUnit<STORAGE_TYPE1, UNIT_TYPE1> first, LLUnit<STORAGE_TYPE2, UNIT_TYPE2> second)
{
- return DERIVED_UNIT(first + LLUnitType<STORAGE_TYPE, BASE_UNIT, DERIVED_UNIT>(second).value());
+ LLUnit<STORAGE_TYPE1, UNIT_TYPE1> result(first);
+ result += second;
+ return result;
}
+template<typename STORAGE_TYPE, typename UNIT_TYPE, typename SCALAR_TYPE>
+LLUnit<STORAGE_TYPE, UNIT_TYPE> operator + (LLUnit<STORAGE_TYPE, UNIT_TYPE> first, SCALAR_TYPE second)
+{
+ LLUnit<STORAGE_TYPE, UNIT_TYPE> result(first);
+ result += second;
+ return result;
+}
-//
-// operator -
-//
-template<typename STORAGE_TYPE, typename BASE_UNIT, typename DERIVED_UNIT, typename STORAGE_TYPE2, typename BASE_UNIT2, typename DERIVED_UNIT2>
-DERIVED_UNIT operator - (typename LLUnitType<STORAGE_TYPE, BASE_UNIT, DERIVED_UNIT>::storage_t first, LLUnitType<STORAGE_TYPE, BASE_UNIT, DERIVED_UNIT> second)
+template<typename STORAGE_TYPE, typename UNIT_TYPE, typename SCALAR_TYPE>
+LLUnit<STORAGE_TYPE, UNIT_TYPE> operator + (SCALAR_TYPE first, LLUnit<STORAGE_TYPE, UNIT_TYPE> second)
{
- return DERIVED_UNIT(first - LLUnitType<STORAGE_TYPE, BASE_UNIT, DERIVED_UNIT>(second).value());
+ LLUnit<STORAGE_TYPE, UNIT_TYPE> result(first);
+ result += second;
+ return result;
}
//
-// operator *
+// operator -
//
-template<typename STORAGE_TYPE, typename BASE_UNIT, typename DERIVED_UNIT>
-DERIVED_UNIT operator * (STORAGE_TYPE first, LLUnitType<STORAGE_TYPE, BASE_UNIT, DERIVED_UNIT> second)
+template<typename STORAGE_TYPE1, typename UNIT_TYPE1, typename STORAGE_TYPE2, typename UNIT_TYPE2>
+LLUnit<STORAGE_TYPE1, UNIT_TYPE1> operator - (LLUnit<STORAGE_TYPE1, UNIT_TYPE1> first, LLUnit<STORAGE_TYPE2, UNIT_TYPE2> second)
{
- return DERIVED_UNIT(first * second.value());
+ LLUnit<STORAGE_TYPE1, UNIT_TYPE1> result(first);
+ result -= second;
+ return result;
}
-template<typename STORAGE_TYPE, typename BASE_UNIT, typename DERIVED_UNIT>
-DERIVED_UNIT operator * (LLUnitType<STORAGE_TYPE, BASE_UNIT, DERIVED_UNIT> first, STORAGE_TYPE second)
+
+template<typename STORAGE_TYPE, typename UNIT_TYPE, typename SCALAR_TYPE>
+LLUnit<STORAGE_TYPE, UNIT_TYPE> operator - (LLUnit<STORAGE_TYPE, UNIT_TYPE> first, SCALAR_TYPE second)
{
- return DERIVED_UNIT(first.value() * second);
+ LLUnit<STORAGE_TYPE, UNIT_TYPE> result(first);
+ result -= second;
+ return result;
}
+template<typename STORAGE_TYPE, typename UNIT_TYPE, typename SCALAR_TYPE>
+LLUnit<STORAGE_TYPE, UNIT_TYPE> operator - (SCALAR_TYPE first, LLUnit<STORAGE_TYPE, UNIT_TYPE> second)
+{
+ LLUnit<STORAGE_TYPE, UNIT_TYPE> result(first);
+ result -= second;
+ return result;
+}
//
-// operator /
+// operator *
//
-template<typename STORAGE_TYPE, typename BASE_UNIT, typename DERIVED_UNIT>
-DERIVED_UNIT operator / (STORAGE_TYPE first, LLUnitTypeWrapper<STORAGE_TYPE, BASE_UNIT, DERIVED_UNIT> second)
+template<typename STORAGE_TYPE, typename UNIT_TYPE, typename SCALAR_TYPE>
+LLUnit<STORAGE_TYPE, UNIT_TYPE> operator * (SCALAR_TYPE first, LLUnit<STORAGE_TYPE, UNIT_TYPE> second)
{
- return DERIVED_UNIT(first / second.value());
+ return LLUnit<STORAGE_TYPE, UNIT_TYPE>(first * second.value());
}
-template<typename STORAGE_TYPE, typename BASE_UNIT, typename DERIVED_UNIT>
-DERIVED_UNIT operator / (LLUnitTypeWrapper<STORAGE_TYPE, BASE_UNIT, DERIVED_UNIT> first, STORAGE_TYPE second)
+template<typename STORAGE_TYPE, typename UNIT_TYPE, typename SCALAR_TYPE>
+LLUnit<STORAGE_TYPE, UNIT_TYPE> operator * (LLUnit<STORAGE_TYPE, UNIT_TYPE> first, SCALAR_TYPE second)
{
- return DERIVED_UNIT(first.value() / second);
+ return LLUnit<STORAGE_TYPE, UNIT_TYPE>(first.value() * second);
}
-//
-// operator <
-//
-template<typename STORAGE_TYPE, typename BASE_UNIT, typename DERIVED_UNIT, typename STORAGE_TYPE2, typename BASE_UNIT2, typename DERIVED_UNIT2>
-
-bool operator < (typename LLUnitType<STORAGE_TYPE, BASE_UNIT, DERIVED_UNIT>::storage_t first, LLUnitType<STORAGE_TYPE, BASE_UNIT, DERIVED_UNIT> second)
+template<typename STORAGE_TYPE1, typename UNIT_TYPE1, typename STORAGE_TYPE2, typename UNIT_TYPE2>
+void operator * (LLUnit<STORAGE_TYPE1, UNIT_TYPE1>, LLUnit<STORAGE_TYPE2, UNIT_TYPE2>)
{
- return first < second.value();
+ llstatic_assert(sizeof(STORAGE_TYPE1) == false, "Multiplication of unit types results in new unit type - not supported.");
}
//
-// operator <=
+// operator /
//
-template<typename STORAGE_TYPE, typename BASE_UNIT, typename DERIVED_UNIT>
-bool operator <= (typename LLUnitType<STORAGE_TYPE, BASE_UNIT, DERIVED_UNIT>::storage_t first, LLUnitType<STORAGE_TYPE, BASE_UNIT, DERIVED_UNIT> second)
+template<typename STORAGE_TYPE, typename UNIT_TYPE, typename SCALAR_TYPE>
+SCALAR_TYPE operator / (SCALAR_TYPE first, LLUnit<STORAGE_TYPE, UNIT_TYPE> second)
{
- return first <= second.value();
+ return SCALAR_TYPE(first / second.value());
}
-
-//
-// operator >
-//
-template<typename STORAGE_TYPE, typename BASE_UNIT, typename DERIVED_UNIT>
-bool operator > (typename LLUnitType<STORAGE_TYPE, BASE_UNIT, DERIVED_UNIT>::storage_t first, LLUnitType<STORAGE_TYPE, BASE_UNIT, DERIVED_UNIT> second)
+template<typename STORAGE_TYPE, typename UNIT_TYPE, typename SCALAR_TYPE>
+LLUnit<STORAGE_TYPE, UNIT_TYPE> operator / (LLUnit<STORAGE_TYPE, UNIT_TYPE> first, SCALAR_TYPE second)
{
- return first > second.value();
+ return LLUnit<STORAGE_TYPE, UNIT_TYPE>(first.value() / second);
}
-//
-// operator >=
-//
-template<typename STORAGE_TYPE, typename BASE_UNIT, typename DERIVED_UNIT>
-bool operator >= (typename LLUnitType<STORAGE_TYPE, BASE_UNIT, DERIVED_UNIT>::storage_t first, LLUnitType<STORAGE_TYPE, BASE_UNIT, DERIVED_UNIT> second)
+template<typename STORAGE_TYPE1, typename UNIT_TYPE1, typename STORAGE_TYPE2, typename UNIT_TYPE2>
+void operator / (LLUnit<STORAGE_TYPE1, UNIT_TYPE1>, LLUnit<STORAGE_TYPE2, UNIT_TYPE2>)
{
- return first >= second.value();
+ llstatic_assert(sizeof(STORAGE_TYPE1) == false, "Multiplication of unit types results in new unit type - not supported.");
}
-//
-// operator ==
-//
-template<typename STORAGE_TYPE, typename BASE_UNIT, typename DERIVED_UNIT>
-bool operator == (typename LLUnitType<STORAGE_TYPE, BASE_UNIT, DERIVED_UNIT>::storage_t first, LLUnitType<STORAGE_TYPE, BASE_UNIT, DERIVED_UNIT> second)
-{
- return first == second.value();
+#define COMPARISON_OPERATORS(op) \
+template<typename STORAGE_TYPE, typename UNIT_TYPE, typename SCALAR_TYPE> \
+bool operator op (SCALAR_TYPE first, LLUnit<STORAGE_TYPE, UNIT_TYPE> second) \
+{ \
+ return first op second.value(); \
+} \
+ \
+template<typename STORAGE_TYPE, typename UNIT_TYPE, typename SCALAR_TYPE> \
+bool operator op (LLUnit<STORAGE_TYPE, UNIT_TYPE> first, SCALAR_TYPE second) \
+{ \
+ return first.value() op second; \
+} \
+ \
+template<typename STORAGE_TYPE1, typename UNIT_TYPE1, typename STORAGE_TYPE2, typename UNIT_TYPE2> \
+bool operator op (LLUnit<STORAGE_TYPE1, UNIT_TYPE1> first, LLUnit<STORAGE_TYPE2, UNIT_TYPE2> second) \
+{ \
+ return first.value() op first.convert(second); \
}
-//
-// operator !=
-//
-template<typename STORAGE_TYPE, typename BASE_UNIT, typename DERIVED_UNIT>
-bool operator != (typename LLUnitType<STORAGE_TYPE, BASE_UNIT, DERIVED_UNIT>::storage_t first, LLUnitType<STORAGE_TYPE, BASE_UNIT, DERIVED_UNIT> second)
+COMPARISON_OPERATORS(<)
+COMPARISON_OPERATORS(<=)
+COMPARISON_OPERATORS(>)
+COMPARISON_OPERATORS(>=)
+COMPARISON_OPERATORS(==)
+COMPARISON_OPERATORS(!=)
+
+namespace LLUnits
{
- return first != second.value();
+#define LL_DECLARE_DERIVED_UNIT(base_unit_name, unit_name, conversion_factor)\
+struct unit_name \
+{ \
+ typedef base_unit_name base_unit_t; \
+}; \
+template<> \
+struct ConversionFactor<unit_name, base_unit_name> \
+{ \
+ static F64 get() { return (conversion_factor); } \
+}; \
+ \
+template<> \
+struct ConversionFactor<base_unit_name, unit_name> \
+{ \
+ static F64 get() { return 1.0 / (conversion_factor); } \
}
-#define LL_DECLARE_BASE_UNIT(unit_name) \
- template<typename STORAGE> \
- struct unit_name : public LLUnitType<STORAGE, unit_name<STORAGE>, unit_name<STORAGE> > \
- { \
- typedef LLUnitType<STORAGE, unit_name> unit_t; \
- \
- unit_name(storage_t value = 0) \
- : LLUnitType(value) \
- {} \
- \
- template <typename SOURCE_STORAGE_TYPE, typename SOURCE_TYPE> \
- unit_name(LLUnitType<SOURCE_STORAGE_TYPE, unit_name<SOURCE_STORAGE_TYPE>, SOURCE_TYPE> source) \
- { \
- assignFrom(source); \
- } \
- \
- template <typename SOURCE_STORAGE_TYPE, typename SOURCE_TYPE> \
- void assignFrom(LLUnitType<SOURCE_STORAGE_TYPE, unit_name<SOURCE_STORAGE_TYPE>, SOURCE_TYPE> source) \
- { \
- setBaseValue((storage_t)source.unit_name<SOURCE_STORAGE_TYPE>::unit_t::value()); \
- } \
- \
- }; \
-
-#define LL_DECLARE_DERIVED_UNIT(base_unit, derived_unit, conversion_factor) \
- template<typename STORAGE> \
- struct derived_unit : public LLUnitType<STORAGE, base_unit<STORAGE>, derived_unit<STORAGE> > \
- { \
- typedef LLUnitType<STORAGE, base_unit<STORAGE>, derived_unit<STORAGE> > unit_t; \
- \
- derived_unit(storage_t value = 0) \
- : LLUnitType(value) \
- {} \
- \
- template <typename SOURCE_STORAGE_TYPE, typename SOURCE_TYPE> \
- derived_unit(LLUnitType<SOURCE_STORAGE_TYPE, base_unit<SOURCE_STORAGE_TYPE>, SOURCE_TYPE> source) \
- { \
- assignFrom(source); \
- } \
- \
- template <typename SOURCE_STORAGE_TYPE, typename SOURCE_TYPE> \
- void assignFrom(LLUnitType<SOURCE_STORAGE_TYPE, base_unit<SOURCE_STORAGE_TYPE>, SOURCE_TYPE> source) \
- { \
- setBaseValue((storage_t)source.base_unit<SOURCE_STORAGE_TYPE>::unit_t::value()); \
- } \
- \
- static F32 conversionToBaseFactor() { return (F32)(conversion_factor); } \
- \
- }; \
-
-namespace LLUnit
-{
- LL_DECLARE_BASE_UNIT(Bytes);
- LL_DECLARE_DERIVED_UNIT(Bytes, Kilobytes, 1024);
- LL_DECLARE_DERIVED_UNIT(Bytes, Megabytes, 1024 * 1024);
- LL_DECLARE_DERIVED_UNIT(Bytes, Gigabytes, 1024 * 1024 * 1024);
- LL_DECLARE_DERIVED_UNIT(Bytes, Bits, (1.f / 8.f));
- LL_DECLARE_DERIVED_UNIT(Bytes, Kilobits, (1024 / 8));
- LL_DECLARE_DERIVED_UNIT(Bytes, Megabits, (1024 / 8));
- LL_DECLARE_DERIVED_UNIT(Bytes, Gigabits, (1024 * 1024 * 1024 / 8));
-
- LL_DECLARE_BASE_UNIT(Seconds);
- LL_DECLARE_DERIVED_UNIT(Seconds, Minutes, 60);
- LL_DECLARE_DERIVED_UNIT(Seconds, Hours, 60 * 60);
- LL_DECLARE_DERIVED_UNIT(Seconds, Days, 60 * 60 * 24);
- LL_DECLARE_DERIVED_UNIT(Seconds, Weeks, 60 * 60 * 24 * 7);
- LL_DECLARE_DERIVED_UNIT(Seconds, Milliseconds, (1.f / 1000.f));
- LL_DECLARE_DERIVED_UNIT(Seconds, Microseconds, (1.f / (1000000.f)));
- LL_DECLARE_DERIVED_UNIT(Seconds, Nanoseconds, (1.f / (1000000000.f)));
-
- LL_DECLARE_BASE_UNIT(Meters);
- LL_DECLARE_DERIVED_UNIT(Meters, Kilometers, 1000);
- LL_DECLARE_DERIVED_UNIT(Meters, Centimeters, 1 / 100);
- LL_DECLARE_DERIVED_UNIT(Meters, Millimeters, 1 / 1000);
+struct Bytes { typedef Bytes base_unit_t; };
+LL_DECLARE_DERIVED_UNIT(Bytes, Kilobytes, 1024);
+LL_DECLARE_DERIVED_UNIT(Bytes, Megabytes, 1024 * 1024);
+LL_DECLARE_DERIVED_UNIT(Bytes, Gigabytes, 1024 * 1024 * 1024);
+LL_DECLARE_DERIVED_UNIT(Bytes, Bits, (1.0 / 8.0));
+LL_DECLARE_DERIVED_UNIT(Bytes, Kilobits, (1024 / 8));
+LL_DECLARE_DERIVED_UNIT(Bytes, Megabits, (1024 / 8));
+LL_DECLARE_DERIVED_UNIT(Bytes, Gigabits, (1024 * 1024 * 1024 / 8));
+
+struct Seconds { typedef Seconds base_unit_t; };
+LL_DECLARE_DERIVED_UNIT(Seconds, Minutes, 60);
+LL_DECLARE_DERIVED_UNIT(Seconds, Hours, 60 * 60);
+LL_DECLARE_DERIVED_UNIT(Seconds, Days, 60 * 60 * 24);
+LL_DECLARE_DERIVED_UNIT(Seconds, Weeks, 60 * 60 * 24 * 7);
+LL_DECLARE_DERIVED_UNIT(Seconds, Milliseconds, (1.0 / 1000.0));
+LL_DECLARE_DERIVED_UNIT(Seconds, Microseconds, (1.0 / (1000000.0)));
+LL_DECLARE_DERIVED_UNIT(Seconds, Nanoseconds, (1.0 / (1000000000.0)));
+
+struct Meters { typedef Meters base_unit_t; };
+LL_DECLARE_DERIVED_UNIT(Meters, Kilometers, 1000);
+LL_DECLARE_DERIVED_UNIT(Meters, Centimeters, (1.0 / 100));
+LL_DECLARE_DERIVED_UNIT(Meters, Millimeters, (1.0 / 1000));
}
#endif // LL_LLUNIT_H