+enum class SIPrefix {
+ unspecified = -1,
+ yocto, zepto,
+ atto, femto, pico,
+ nano, micro, milli,
+ none,
+ kilo, mega, giga,
+ tera, peta, exa,
+ zetta, yotta
+};
+
+/// Returns the exponent that corresponds to a given prefix.
+int exponent(SIPrefix prefix);
+
+/// Timestamp type providing yoctosecond resolution.
+typedef boost::multiprecision::number<
+ boost::multiprecision::cpp_dec_float<24>,
+ boost::multiprecision::et_off> Timestamp;