diff --git a/src/compiler/GF/Command/Commands.hs b/src/compiler/GF/Command/Commands.hs
index 718874d0c..0e5c61404 100644
--- a/src/compiler/GF/Command/Commands.hs
+++ b/src/compiler/GF/Command/Commands.hs
@@ -34,6 +34,7 @@ import Data.Maybe
 import qualified Data.Map as Map
 import GF.Text.Pretty
 import Data.List (sort)
+import qualified Control.Monad.Fail as Fail
 --import Debug.Trace
 
 
@@ -44,7 +45,7 @@ pgfEnv pgf = Env pgf mos
 
 class (Functor m,Monad m,MonadSIO m) => HasPGFEnv m where getPGFEnv :: m PGFEnv
 
-instance (Monad m,HasPGFEnv m,MonadFail m) => TypeCheckArg m where
+instance (Monad m,HasPGFEnv m,Fail.MonadFail m) => TypeCheckArg m where
   typeCheckArg e = (either (fail . render . ppTcError) (return . fst)
                     . flip inferExpr e . pgf) =<< getPGFEnv
 
diff --git a/src/compiler/GF/Command/Commands2.hs b/src/compiler/GF/Command/Commands2.hs
index 6d326cdce..100f877a9 100644
--- a/src/compiler/GF/Command/Commands2.hs
+++ b/src/compiler/GF/Command/Commands2.hs
@@ -18,6 +18,7 @@ import Data.Maybe
 import qualified Data.Map as Map
 import GF.Text.Pretty
 import Control.Monad(mplus)
+import qualified Control.Monad.Fail as Fail
 
 
 data PGFEnv = Env {pgf::Maybe PGF,concs::Map.Map ConcName Concr}