This is a module for doing integer arithmetic in arbitrary base
representations. A representation, or "flex", is determined by
what symbols you use for +, -, and the digits. The base that
you are working in is the number of digits you use to represent
your numbers. Given a flex it can do the following:
o Convert string representations of numbers to a convenient
internal form for calculations as needed.
o Convert from one internal representation to another,
transparently changing bases as required.
o Write the internal representation back to a string.
o Handle large integer arithmetic.
A sample use would be to write 128 bit MD5 hashes using whatever
set of characters you want.