From: Wayne Scott <wscott / ichips.intel.com>
> I just realized that the '[]=' is not implimented for Fixnum and Bignum.
> Add that to my feature request. :)

I bet you can't impliment '[]=' for Fixnum because it is an immediate
value right?

Even Bignum would be a problem:

a = 44
b = a
 
a[4] = 1    # this changes 'b' as well as 'a'

Assuming the above is correct, I need to rethink wanting to write BitFields.

-Wayne