--pretend & --fetch-all options

[Glen Whitney]

Quoting from macports-users 20 Feb 2007:
>> That said, it still remains second to the first idea
>> of mel who started this thread, to implement a dry
>> run feature. Maybe, dry run would just be half of
>> the implementation of prefetch.
> 
> Due to the reason above, I'd prefer the the dry run feature
> to be implemented first, because I think in the long run
> it will help to improve port's variants feature.

I have submitted a patch (dry.3.patch attached to 
http://trac.macports.org/projects/macports/ticket/11892)
against the current svn version (r24893) which adds a -y option
for dry run. (I chose -y since it's the only letter left from "dry" 
which was not already an option.) It turns out to be a pretty simple 
patch, only touching one tcl source file except for documentation and 
parsing the switch. I now use it all the time for checking out recursive 
dependencies and the behavior of different variants.  Perhaps it will 
catch the eye of someone who can incorporate it into the development 
version of MacPorts.

Hope this is helpful,
      Glen Whitney