[MacPorts] #37075: boost: add "default_variants +python27" (was: please consider adding "default_variants +python27" to boost)

[MacPorts]

#37075: boost: add "default_variants +python27"
--------------------------+---------------------------
  Reporter:  mmoll@…      |      Owner:  adfernandes@…
      Type:  enhancement  |     Status:  closed
  Priority:  Normal       |  Milestone:
 Component:  ports        |    Version:
Resolution:  fixed        |   Keywords:
      Port:  boost        |
--------------------------+---------------------------
Changes (by ryandesign@…):

 * cc: ryandesign@… (added)


Comment:

 Replying to [comment:2 adfernandes@…]:
 > Done (r99960).

 You shouldn't unconditionally make +python27 the default variant; it makes
 it hard for users who want a different python variant:

 {{{
 $ sudo port install boost +python26
 Password:
 Error: boost: Variant python26 conflicts with python27
 Error: Unable to open port: Error evaluating variants
 }}}

 Usually you would follow wiki:PortfileRecipes#default_variants for this
 but the boost port is more unusual in that it constructs variants in a for
 loop. Fixed in r100008 using a method I found in the alps port.

 See also #37111.

 > Want to bet that there are complaints that python3 isn't a default...?
 :-)

 python27 is the default python in MacPorts. Any desire to change that
 should be discussed and agreed upon on the dev mailing list.


 Replying to [comment:3 mmoll@…]:
 > Thanks! Could you also bump the revision to force a rebuild by the build
 bot?

 Increasing the revision solely to make the buildbot rebuild is not a good
 idea; see [http://lists.macosforge.org/pipermail/macports-
 dev/2012-November/021096.html mailing list].

 In this case increasing the revision also has the effect of ensuring
 anybody who did not have a python variant selected will now have python27
 selected. This also seems not essential. Anyone who really needed python27
 would have selected it manually by now. And by adding it to
 default_variants, anyone else will get it next time they rebuild, for
 example when the next version of boost is released. So if I had it to do
 over again I would not have imposed this rebuild on users and would not
 have increased the revision.


 Replying to [comment:4 adfernandes@…]:
 > Grumble. I need to add +openmpi, so I can't use the buildbot version...
 and rebuilding boost makes my electricity bill double!

 You don't have to upgrade a port, of course; you can wait until the next
 version or whenever.

-- 
Ticket URL: <https://trac.macports.org/ticket/37075#comment:5>
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