From: Christian Szegedy <szegedy@...>
Date: 2002-09-11T01:34:34+09:00
Subject: Re: Addition on appropriate fields...

Christopher Browne wrote:


> Anyone that has studied abstract algebra _won't_ be overly confused by
> this, as the first entry into group theory will leap you into addition
> systems that don't work the way you used to expect.

I never heard about "noncommutative sum" in algebra. I think in
every algabraic structure, the sum is commutative. E.g. in Group
Theory, the group opertion is denoted by + as long as the group is
Abelian, that is commutative but it is always denoted by * for
noncommutative groups.

I, as a mathematician, still find it very intuitive and natural to
denote the concatenation of strings by "+". I have no problems with
it and this would be the last thing I would change in Ruby.


> b) 2147352576 + 175000 often will not add up to 2147527576 unless you
      are using Common Lisp, where that can revert to a BIGNUM.

.... or Ruby ...

Regards, Christian