Creating User-Defined Types.

[boops boops]

Why not? its just:
Bigint: 42472435720345002047520000000000000000000000000000000000000000000000000000000000000000314159265
Dec: 73

The way I see it, the purpose of the BigDecimal (now my preferred name again) is to allow calculations with accurate intermediate values. Having an output with a huge number of decimal places would be wanted only rarely -- say for testing purposes, to impress your boss, or to satisfy Pi mystics. The default ToString representation could be similar to Double but with a larger exponent range. For example:

4247243572034500204752 * 10^500577832

Of course there should be an option to output more decimal places in the mantissa when required.

BB