diff --git a/Dvda/Expr.hs b/Dvda/Expr.hs
--- a/Dvda/Expr.hs
+++ b/Dvda/Expr.hs
@@ -24,6 +24,7 @@
                  , substitute
                  , sketchySubstitute
                  , foldExpr
+                 , fromNeg
                  ) where
 
 import Control.Applicative ( (<$>), (<*>), pure )
diff --git a/dvda.cabal b/dvda.cabal
--- a/dvda.cabal
+++ b/dvda.cabal
@@ -1,5 +1,5 @@
 Name:                dvda
-Version:             0.3.1
+Version:             0.3.2
 License:             BSD3
 License-file:        LICENSE
 Author:              Greg Horn