This is at least documented in the manual (
http://caml.inria.fr/pub/docs/manual-ocaml/libref/Pervasives.html ):
  > Note that x mod y is negative only if x < 0.

I suppose the idea was to make the least surprising choice (assuming people
knew , and also have the behavior coincide with mod_float. (Interestingly,
the IEEE754 norm requires a "remainder" operation that has an even stranger
behavior (modulo is defined from the round-to-nearest division) and I
haven't proposed anywhere.)

On Sun, Jan 18, 2015 at 7:48 PM, Hannes Mehnert <hannes@mehnert.org> wrote:

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> Hi,
>
> is the behaviour of modulo arithmetics intentional:
>  -5 mod 4 = -1 ?
>
> While this reflects the C behaviour, my expectation was to always have
> a positive result:
>  -5 mod 4 = 3
>
> Any hints?
>
> hannes
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