[MacPorts] #15712: Add versions to platforms

[MacPorts]

#15712: Add versions to platforms
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  Reporter:  raimue       |      Owner:  larryv
      Type:  enhancement  |     Status:  assigned
  Priority:  Normal       |  Milestone:  MacPorts 2.6.0
 Component:  base         |    Version:
Resolution:               |   Keywords:
      Port:               |
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Comment (by raimue):

 Regarding `darwin` vs. `macosx`: the keyword is "require". Most of the
 other ports will also build without Apple Frameworks, but will use them if
 available. Applications with a native GUI will choose `macosx`, as they
 cannot work without Apple Frameworks.

 As I see it, the guide is correct. Maybe it is not properly phrased, but
 `darwin` means any of `macosx` or `puredarwin` and these are not the same.
 They are also not handled the same in MacPorts base, which has the notion
 of `macosx` and `puredarwin` each being a subplatform of `darwin`. See
 `${os.subplatform}`.

 I agree that the specification is to exclude platforms. However, we always
 list the working cases. We also have `supported_archs` and not
 `broken_archs`.

 I do not think we need a way to express the reason why a port is broken. A
 comment in the Portfile should suffice. If someone encounters an
 unsupported platform and want to look into it, they will find the comment
 anyway.

-- 
Ticket URL: <https://trac.macports.org/ticket/15712#comment:39>
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