[MacPorts] #20053: Document the port naming convention of replacing ++ with xx

[MacPorts]

#20053: Document the port naming convention of replacing ++ with xx
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  Reporter:  blb@…   |      Owner:  markd@…
      Type:  defect  |     Status:  new
  Priority:  Normal  |  Milestone:
 Component:  guide   |    Version:  1.8.0
Resolution:          |   Keywords:
      Port:          |
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Comment (by khindenburg@…):

 I think this can be closed

 https://guide.macports.org/#reference.keywords

 {{{
 The name of the port. To avoid special interpretation by shells and the
 like, names should contain
 only alphanumeric characters, underscores, dashes or dots. For projects
 whose proper names
 contain “+” characters, change these to “x” (i.e. “libstdc++” becomes
 “libstdcxx”).
 }}}

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Ticket URL: <https://trac.macports.org/ticket/20053#comment:4>
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