diff --git a/src-derived/PrintCode.hs b/src-derived/PrintCode.hs
--- a/src-derived/PrintCode.hs
+++ b/src-derived/PrintCode.hs
@@ -1534,7 +1534,7 @@
                                 rightOp x y = if onLeftSide_
                                               then x
                                               else x `op` y
-                            in pragmaDoc `leftOp` _exprIpp `rightOp` pragmaDoc
+                            in pp_parens (pragmaDoc `leftOp` _exprIpp `rightOp` pragmaDoc)
                             {-# LINE 1539 "PrintCode.hs" #-}) of
                       { !_lhsOpp ->
                       ( _lhsOpp) }) }) }) }) })) )
diff --git a/src/Version.hs b/src/Version.hs
--- a/src/Version.hs
+++ b/src/Version.hs
@@ -1,4 +1,4 @@
 module Version where
 
 banner :: String
-banner = "Attribute Grammar compiler / HUT project. Version 0.9.19"
+banner = "Attribute Grammar compiler / HUT project. Version 0.9.20"
diff --git a/uuagc.cabal b/uuagc.cabal
--- a/uuagc.cabal
+++ b/uuagc.cabal
@@ -1,7 +1,7 @@
 cabal-version: >=1.2
 build-type: Simple
 name: uuagc
-version: 0.9.19
+version: 0.9.20
 license: GPL
 license-file: LICENSE
 maintainer: Arie Middelkoop <ariem@cs.uu.nl>
diff --git a/uuagc.cabal-for-ghc-6.6 b/uuagc.cabal-for-ghc-6.6
--- a/uuagc.cabal-for-ghc-6.6
+++ b/uuagc.cabal-for-ghc-6.6
@@ -1,5 +1,5 @@
 name: uuagc
-version: 0.9.19
+version: 0.9.20
 license: GPL
 license-file: LICENSE
 maintainer: Arie Middelkoop <ariem@cs.uu.nl>