diff --git a/src/TTImp/Elab/App.idr b/src/TTImp/Elab/App.idr
index 066c729b8..0b9f8578c 100644
--- a/src/TTImp/Elab/App.idr
+++ b/src/TTImp/Elab/App.idr
@@ -836,12 +836,13 @@ checkApp rig elabinfo nest env fc (IVar fc' n) expargs autoargs namedargs exp
 
         boundSafe : Constant -> ElabMode -> Bool
         boundSafe _ (InLHS _) = True -- always need to expand on LHS
-        boundSafe (BI x) _ = abs x < 100 -- only do this for relatively small bounds.
-                           -- Once it gets too big, we might be making the term
-                           -- bigger than it would have been without evaluating!
+        -- only do this for relatively small bounds.
+        -- Once it gets too big, we might be making the term
+        -- bigger than it would have been without evaluating!
+        boundSafe (BI x) _ = abs x < 100
+        boundSafe (Str str) _ = length str < 10
         boundSafe _ _ = True
 
-
     updateElabInfo : List Name -> ElabMode -> Name ->
                      List RawImp -> ElabInfo -> Core ElabInfo
     -- If it's a primitive function applied to a constant on the LHS, treat it