[plt-dev] Re: [plt-scheme] SchemeUnit confusion

From: Dave Gurnell (d.j.gurnell at gmail.com)
Date: Tue Jun 9 05:10:58 EDT 2009

 From an app developer's point of view, I think Noel's reasoning is  

All of PLT is bundled together under one big version number. If you  
upgrade the core, you upgrade all the satellite libraries as well.  
This has three drawbacks:

   - if you want to upgrade to a newer version of PLT for an  
improvement in one library, you may have to deal with potential  
backwards-incompatible changes in other libraries at the same time;

   - compiling all of PLT can be slow;

   - other software you have developed may still use older versions of  

PLaneT offers a little more flexibility: to a certain degree you can  
choose to upgrade one dependency independently of the rest.

In other words, if Noel makes a change to Schemeunit, and a developer  
is requiring it from the core, he/she will have to update all of PLT  
at the same time, which might take a while and make upgrading  
difficult. If, however, the developer is requiring Schemeunit from  
PLaneT, they should hopefully be able to just upgrade that one library  
and leave everything else as-is.


-- Dave

> Noel, I don't understand this response at all. Could you elaborate?  
> In the past we have deprecated planet package when we moved code  
> into the core. -- Matthias
>> Dependency management. We've been bitten by changes in the web server
>> stopping us upgrading PLT to get bug fixes in other areas. Now
>> SchemeUnit isn't as likely to change as the web server, but why make
>> the dependency if you can avoid it? (This only applies if you aren't
>> developing core code. If you are, use the core version.)
>> N.
>>> Why recommend the planet version over the core version?
>>> Robby

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