public QualifiedQuantity(string value, out string remainder)
{
if (Char.IsLetter(value[0]))
{
string q = Physical.NextWord(value, out remainder);
if (!Physical.IsQualifier(q))
throw new Exception(String.Format("Unknown Qualifier: {0}", q));
_hasQualifier = Enum.TryParse(q, true, out _qualifier);
}
_anyQuantity = new Quantity(value, out remainder);
}