module dependency

[Joe Wang]

Alan Bateman wrote:
> Joe Wang wrote:
>> Hi,
>>
>> I have a question about the module system's support on module 
>> dependencies. A module can specify that it "require" or depends on 
>> other modules. Is it possible to express the sort of one to many 
>> relationship in that M4 requires M1 or M2 or M3 and at least one of 
>> them. If that's possible, it would also be nice to be able to find 
>> out, through a jigsaw interface, which module (of M1, M2 and M3) has 
>> been installed by querying M4 (by module name or id). Is this possible?
>>
>> Thanks,
>> Joe
> This is JAXP, right? Do M1, M2, and M3 provide alternative 
> implementations of a module that M4 requires? If so then the virtual 
> module support may help with some of this.
Yes, it's JAXP. 

For the virtual module, do I understand correctly, that we would add a 
"virtual module", e.g. VM, and define each of the three modules to 
"provide" it, thus making it possible for M4 to rely on VM? Will there 
be a way for M4 to determine which of the three modules has been installed?

Joe
>
> -Alan.