Merge remote-tracking branch 'remotes/misandrist/FreeBSD' into wip

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diff --git a/doc/forum/howto_mapM_RevertableProperty/comment_1_c2800340a5361add82f5e9e30b56b18c._comment b/doc/forum/howto_mapM_RevertableProperty/comment_1_c2800340a5361add82f5e9e30b56b18c._comment
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+[[!comment format=mdwn
+ username="joey"
+ subject="""comment 1"""
+ date="2016-02-08T15:00:26Z"
+ content="""
+combineProperties takes a list of PropertyListType, which is a type family
+consisting of [Property NoInfo] and [Property HasInfo]. So, you need to get
+from RevertableProperty NoInfo to one of those. `toProp` can do that.
+
+	combineProperties "desc" (map (toProp . myProperty) confs)
+
+But! I had a look and it was easy to make [RevertableProperty i] an
+instance of PropertyListType, which makes what you already tried type check
+too. I've done so in git.
+
+It would perhaps be nice to make lists of various sorts of properties
+instances of Traversable, so that mapM etc could be used over them. That
+would need some kind of monad for combining properties though, which does
+not currently exist. Might make more sense to make an instance of Foldable
+or just Monoid for properties. Any improvements in this area would be
+appreciated!
+"""]]
diff --git a/doc/forum/howto_mapM_RevertableProperty/comment_2_1327f1f218433ce262f871771c43452c._comment b/doc/forum/howto_mapM_RevertableProperty/comment_2_1327f1f218433ce262f871771c43452c._comment
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+[[!comment format=mdwn
+ username="picca"
+ subject="comment 2"
+ date="2016-02-10T06:41:49Z"
+ content="""
+Thanks a lot joey :)
+
+I am learning haskell for now and I am not very confortable yet with the haskell Monoid, functor, applicative and monad.
+
+So what you are saying is that it would be great to do something like
+
+    instance monoid Property where
+         mempty = doNothing
+         mappend p1 p2 = combineProperty [p1, p2]
+         mconcat ps = combineProperty ps
+
+in order to combine properties.
+my question is why did you choose to create combineProperty instead of a Monoid at first ?
+
+thanks
+
+Frederic
+"""]]
diff --git a/doc/forum/howto_mapM_RevertableProperty/comment_3_7e519cc5f1c07b66561ec31866ddbc8a._comment b/doc/forum/howto_mapM_RevertableProperty/comment_3_7e519cc5f1c07b66561ec31866ddbc8a._comment
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+[[!comment format=mdwn
+ username="joey"
+ subject="""comment 3"""
+ date="2016-02-10T16:09:08Z"
+ content="""
+Would probably be better to use `before`, since `combineProperties`
+needs a description of the combined properties.
+
+Using `doNothing` is kind of a hack, it would make propellor say it was
+running "noop property". Perhaps better to use a SemiGroup than a Monoid.
+"""]]