From: Johann Hibschman <johann@...>
Date: 2001-05-08T06:11:25+09:00
Subject: [ruby-talk:14813] Re: Integer division oddness

Mike T Miller writes:

> My father pointed out this oddity.
> Using integer math, try this on various languages:

> -10 / 9

> For ruby, python and tcl you get: -2!
> For java, c and gforth you get:   -1

IMHO, the ruby and python result is the correct one, although I still
don't like it.  This is one place where java, c, and gforth are just
broken.  Things get weird if you were considering "10 / -9" or "-10 /
-9", but for "-10 / 9", there is only one right answer, and that's -2.

The link you posted gets to the heart of the matter.  Luckily, both
python and ruby have a divmod function, which makes things quite
explicit.

Of course, I'd prefer it if "/" produced rationals and forced
people to use "div" when they meant div.  Integer division just
doesn't exist, since the integers are a ring and not a field.

Grumble.  Grumble.  Why can't more languages get this right?

--Johann

-- 
Johann Hibschman                           johann@physics.berkeley.edu