[MacPorts] #15712: Add versions to platforms

[MacPorts]

#15712: Add versions to platforms
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 Reporter:  raimue at macports.org  |       Owner:  macports-tickets at lists.macosforge.org
     Type:  enhancement          |      Status:  new                                  
 Priority:  Normal               |   Milestone:  MacPorts base enhancements           
Component:  base                 |     Version:                                       
 Keywords:  platforms versions   |  
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 Currently the `platforms` statement can only specify a platform like
 `darwin, macosx, linux, freebsd` and others, but cannot require a version
 of the platform. So this is a proposal to extend it to also include
 platform version numbers.

 This would look like this:
 {{{
 platforms    darwin                  # as it is now
 platforms    {darwin 7} {darwin 8}   # Darwin 7 or 8
 platforms    {darwin >=8}            # Darwin 8 or higher
 platforms    {macosx >=9.3}          # Mac OS X 10.5.3 or higher
 }}}

 If a platform does not match the requirements, the port should error out
 automatically when trying to install it. To enforce a specifc version,
 some ports are using pre-fetch {} blocks at the moment, these could be
 replaced with this new syntax.

-- 
Ticket URL: <http://trac.macports.org/ticket/15712>
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