diff --git a/haddock-library/test/Documentation/Haddock/ParserSpec.hs b/haddock-library/test/Documentation/Haddock/ParserSpec.hs
index 7df9dab2a66962fc9ebe488c3ec47effb58c4893..4fea255a68e91baa8c4b1a839f057c696a69bb19 100644
--- a/haddock-library/test/Documentation/Haddock/ParserSpec.hs
+++ b/haddock-library/test/Documentation/Haddock/ParserSpec.hs
@@ -12,6 +12,7 @@ import           Test.Hspec
 import           Test.QuickCheck
 
 infixr 6 <>
+(<>) :: Doc id -> Doc id -> Doc id
 (<>) = docAppend
 
 type Doc id = DocH () id