values including \constant{NaN}, \constant{sNaN}, \constant{-Infinity},
\constant{Infinity}, and two zeroes, \constant{+0} and \constant{-0}.
-Infinities can constructed directly with: \code{Decimal('Infinity')}. Also,
+Infinities can be constructed directly with: \code{Decimal('Infinity')}. Also,
they can arise from dividing by zero when the \exception{DivisionByZero}
signal is not trapped. Likewise, when the \exception{Overflow} signal is not
trapped, infinity can result from rounding beyond the limits of the largest