nixpkgs/pkgs/development/haskell-modules/diagrams-lib-flexible-contexts.patch

diff -Naur diagrams-lib-1.2.0.9-orig/src/Diagrams/TwoD/Polygons.hs diagrams-lib-1.2.0.9/src/Diagrams/TwoD/Polygons.hs
--- diagrams-lib-1.2.0.9-orig/src/Diagrams/TwoD/Polygons.hs	2015-04-02 22:13:26.000000000 -0400
+++ diagrams-lib-1.2.0.9/src/Diagrams/TwoD/Polygons.hs	2015-04-11 18:17:28.095156620 -0400
@@ -4,6 +4,7 @@
 {-# LANGUAGE TemplateHaskell           #-}
 {-# LANGUAGE TypeFamilies              #-}
 {-# LANGUAGE ViewPatterns              #-}
+{-# LANGUAGE FlexibleContexts          #-}
 
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