[commit: ghc] master: Add Outputable instance for Node (6e890e8)

[git at git.haskell.org]

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

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/6e890e8c9b960805c87268e9b3ce2e3d4a58297b/ghc

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

commit 6e890e8c9b960805c87268e9b3ce2e3d4a58297b
Author: Matthew Pickering <matthewtpickering at gmail.com>
Date:   Thu May 11 15:42:02 2017 -0400

    Add Outputable instance for Node
    
    Reviewers: austin, bgamari
    
    Reviewed By: bgamari
    
    Subscribers: rwbarton, thomie
    
    Differential Revision: https://phabricator.haskell.org/D3564


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6e890e8c9b960805c87268e9b3ce2e3d4a58297b
 compiler/utils/Digraph.hs | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/compiler/utils/Digraph.hs b/compiler/utils/Digraph.hs
index fe325e6..e3b5037 100644
--- a/compiler/utils/Digraph.hs
+++ b/compiler/utils/Digraph.hs
@@ -99,6 +99,9 @@ data Node key payload = DigraphNode {
      --    it's ok to have extra keys in the dependencies that
      --    are not the key of any Node in the graph
 
+instance (Outputable a, Outputable b) => Outputable (Node  a b) where
+  ppr (DigraphNode a b c) = ppr (a, b, c)
+
 emptyGraph :: Graph a
 emptyGraph = Graph (array (1, 0) []) (error "emptyGraph") (const Nothing)