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gaussian rationals

Frankly, complex arithmetic should not be designed by a consensus of Lisp
hackers.  The difference between mathematical theory and computation
is perhaps not clear to Alan, but there is a difference between thinking
mathematically and computationally.  For example, division by 0 is not
defined in a mathematical field.  Computationally, division by 0 must
be treated SOME way.  Similarly, -1 and -1+0*i can be said to be mathematically
identical, but that says very little about how to compute with them.
In particular, whether sqrt(*) gives an error or not.  One view of
sqrt(-4)  is that it should return -2.  The sign of the answer clearly indicates
something funny went on.

I would propose that rather than vote on complex arithmetic in this forum,
real arithmetic only be specified, and allow someone at some later
time specify a package for complex.