What data types are used?
While any subclasses of Number can be "passed in" via the Context, most operations
will result in values of type BigDecimal, BigInteger, or Boolean. Generally, values
are promoted from BigInteger to BigDecimal only when one of the operands is a BigDecimal,
however this is not true for division, which alwayse uses BigDecimal.
What guarantees are provided?
None. Simple operations like plus, minus, multiply and divide use the functionality
provided by Java's BigDecimal and BigInteger, and are probably very safe. Other
functions, like sin(), cos(), tan() and sqrt() do more complex processing.
Most functions that could be were tested and compaired against
their java.lang.Math counterparts.