[gecode-users] non empty rangelist with an empty range

[Denys Duchier]

I wrote:

    SetVar s(this, 0, -1, 0, 10, 0, 11);

because it seemed (I guess, by analogy with loops) a fairly natural way
to indicate an empty glb.  It turns out that Gecode will happily create
a range list containing the range [0,-1] which causes Gecode to behave
strangely.

I think that either the documentation should explicitely state the
invariant or the code should check it.

Cheers,

--Denys