On Nov 1, 2007, at 12:26 AM, Andreas Raab wrote:

> Brian Brown wrote:
>> Hi Chris - I think you are missing one of the main points of the  
>> Universe model. Universes do not pick the "most recent version of  
>> anything. A particular universe has pointers to specific code  
>> packages, i.e. specific mcz files which represent one and only one  
>> version of that piece of code. There is nothing dynamic about it,  
>> so it is really like a freebsd port or debian package - you have to  
>> have specific version of the dependencies that port or package  
>> needs, not just the "latest".
>
> That is *definitely* not true. The code in  
> UUniverseBrowser>>allPackagesNeededToInstall:orIfImpossible:  
> explicitly uses the *latest* version of a package; the basic loop  
> goes like this:
>
>  package depends do: [ :depName |
>    "... some code omitted for brevity ..."
>   (universe hasPackageNamed: depName) ifTrue: [
>     packagesToConsider add: (universe newestPackageNamed: depName)
>   ].
>
> and #newestPackageNamed: does just what it says:
>
> newestPackageNamed: name
>  | potentials sorted |
>  potentials _ self packagesNamed: name.
>  sorted _ potentials asSortedCollection: [ :p1 :p2 | p1 version < p2  
> version ].
>  ^sorted last

Well, obviously a gross misunderstanding on my part, based on Lex's  
initial discussions and further clarifications on what Universes are  
supposed to be. I did not look at the code to verify that, but was  
arguing from what I had gathered from the discussion.

In light of the actual code, I have to retract what I said, with  
apologies.

Thanks for pointing this out!


>
>
>> "Guaranteed to work together" means that the author of the Universe  
>> has ostensibly tested that the specific package versions in that  
>> Universe do in fact work together. Since it is NOT grabbing "the  
>> latest code", that is a claim a Universe can make.
>
> Given the above, how can it?
>

Agreed ;)

> Cheers,
>  - Andreas
>