[MacPorts] #44526: xxdiff: update to 4.0

[MacPorts]

#44526: xxdiff: update to 4.0
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  Reporter:  RJVB    |      Owner:  macports-tickets@…
      Type:  update  |     Status:  new
  Priority:  Normal  |  Milestone:
 Component:  ports   |    Version:
Resolution:          |   Keywords:  haspatch
      Port:  xxdiff  |
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Comment (by RJVB):

 What you are missing is that the changes proposed in this ticket were
 never integrated, and I have basically abandoned it in favour of my own
 fork (and custom port).

 The official 4.0.1 version does have most of my contributions included, so
 it should be straightforward for you to check out the sources and then
 build them against the required dependents from your MacPorts install. if
 you do, I'd strongly suggest to build against Qt5.

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Ticket URL: <https://trac.macports.org/ticket/44526#comment:22>
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