[commit: ghc] master: Add haddock for Node in Digraph. [skip ci] (c5ced67)

[git at git.haskell.org]

Repository : ssh://git@git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/c5ced679a6f5421eb53acf1fd1d212088145c971/ghc

>---------------------------------------------------------------

commit c5ced679a6f5421eb53acf1fd1d212088145c971
Author: klebinger.andreas at gmx.at <klebinger.andreas at gmx.at>
Date:   Fri Dec 7 23:22:08 2018 -0500

    Add haddock for Node in Digraph. [skip ci]
    
    Test Plan: make
    
    Reviewers: bgamari
    
    Reviewed By: bgamari
    
    Subscribers: rwbarton, carter
    
    Differential Revision: https://phabricator.haskell.org/D5378


>---------------------------------------------------------------

c5ced679a6f5421eb53acf1fd1d212088145c971
 compiler/utils/Digraph.hs | 24 ++++++++++++++++--------
 1 file changed, 16 insertions(+), 8 deletions(-)

diff --git a/compiler/utils/Digraph.hs b/compiler/utils/Digraph.hs
index bb118a6..cb401be 100644
--- a/compiler/utils/Digraph.hs
+++ b/compiler/utils/Digraph.hs
@@ -87,15 +87,23 @@ data Graph node = Graph {
 
 data Edge node = Edge node node
 
+{-| Representation for nodes of the Graph.
+
+ * The @payload@ is user data, just carried around in this module
+
+ * The @key@ is the node identifier.
+   Key has an Ord instance for performance reasons.
+
+ * The @[key]@ are the dependencies of the node;
+   it's ok to have extra keys in the dependencies that
+   are not the key of any Node in the graph
+-}
 data Node key payload = DigraphNode {
-      node_payload :: payload,
-      node_key :: key,
-      node_dependencies :: [key] }
-     -- The payload is user data, just carried around in this module
-     -- The keys are ordered
-     -- The [key] are the dependencies of the node;
-     --    it's ok to have extra keys in the dependencies that
-     --    are not the key of any Node in the graph
+      node_payload :: payload, -- ^ User data
+      node_key :: key, -- ^ User defined node id
+      node_dependencies :: [key] -- ^ Dependencies/successors of the node
+  }
+
 
 instance (Outputable a, Outputable b) => Outputable (Node  a b) where
   ppr (DigraphNode a b c) = ppr (a, b, c)