Case - class from required module is not available

[Alan Bateman]

On 28/03/2012 02:48, David Holmes wrote:
> On 28/03/2012 3:53 AM, Mandy Chung wrote:
>> This is an interesting scenario - module c is linked with module b only
>> whereas module d is linked with module a only.
>
> So is that a bug or a feature? Given b will not be able to find a<1.0, 
> but a1.0 is already loaded, is it then necessary that b not be linked 
> to d?
Right, a at 1.0 and b at 1.0 can't be the same configuration because of the 
constraint so the answer for d has to be {d at 1.0, a at 1.0} or {d at 1.0, 
b at 1.0}. There is code in the resolver that ensures that the dependencies 
are examined in order so I assume this is why {d at 1.0, a at 1.0} is chosen. 
If d's dependencies are reversed then it will generate the other answer. 
With c then the answer has to be {c at 1.0, b at 1.0}.

-Alan.