diff --git a/src/bin/cli_helpers.ml b/src/bin/cli_helpers.ml
index ee757ffba..7057e0975 100644
--- a/src/bin/cli_helpers.ml
+++ b/src/bin/cli_helpers.ml
@@ -10,7 +10,7 @@ let toplevel ~(display_format : string) (x : string result) =
       )
   in
   match x with
-  | Ok _ -> Format.printf "%a" (formatted_string_result_pp display_format) x
+  | Ok _ -> Format.printf "%a\n%!" (formatted_string_result_pp display_format) x
   | Error _ ->
-     Format.eprintf "%a" (formatted_string_result_pp display_format) x ;
+     Format.eprintf "%a\n%!" (formatted_string_result_pp display_format) x ;
      exit 1
diff --git a/src/passes/operators/operators.ml b/src/passes/operators/operators.ml
index 6568b2863..ceb17f17a 100644
--- a/src/passes/operators/operators.ml
+++ b/src/passes/operators/operators.ml
@@ -703,6 +703,7 @@ module Compiler = struct
     ("MAP_UPDATE" , simple_ternary @@ prim I_UPDATE) ;
     ("SIZE" , simple_unary @@ prim I_SIZE) ;
     ("FAILWITH" , simple_unary @@ prim I_FAILWITH) ;
+    ("ASSERT_INFERRED" , simple_binary @@ i_if (seq [i_failwith]) (seq [i_drop ; i_push_unit])) ;
     ("ASSERT" , simple_unary @@ i_if (seq [i_push_unit]) (seq [i_push_unit ; i_failwith])) ;
     ("INT" , simple_unary @@ prim I_INT) ;
     ("ABS" , simple_unary @@ prim I_ABS) ;
diff --git a/src/test/contracts/coase.ligo b/src/test/contracts/coase.ligo
index b1f1da4a4..ea7f9d057 100644
--- a/src/test/contracts/coase.ligo
+++ b/src/test/contracts/coase.ligo
@@ -41,7 +41,7 @@ function transfer_single(const action : action_transfer_single ; const s : stora
   begin
     const cards : cards = s.cards ;
     const card : card = get_force(action.card_to_transfer , cards) ;
-    if (card.card_owner =/= source) then failwith("This card doesn't belong to you") else skip ;
+    if (card.card_owner =/= source) then fail "This card doesn't belong to you" else skip ;
     card.card_owner := action.destination ;
     cards[action.card_to_transfer] := card ;
     s.cards := cards ;
@@ -51,7 +51,7 @@ function transfer_single(const action : action_transfer_single ; const s : stora
 function sell_single(const action : action_sell_single ; const s : storage_type) : (list(operation) * storage_type) is
   begin
     const card : card = get_force(action.card_to_sell , s.cards) ;
-    if (card.card_owner =/= source) then failwith("This card doesn't belong to you") else skip ;
+    if (card.card_owner =/= source) then fail "This card doesn't belong to you" else skip ;
     const card_pattern : card_pattern = get_force(card.card_pattern , s.card_patterns) ;
     card_pattern.quantity := abs(card_pattern.quantity - 1n);
     const card_patterns : card_patterns = s.card_patterns ;
@@ -71,7 +71,7 @@ function buy_single(const action : action_buy_single ; const s : storage_type) :
     // Check funds
     const card_pattern : card_pattern = get_force(action.card_to_buy , s.card_patterns) ;
     const price : tez = card_pattern.coefficient * (card_pattern.quantity + 1n) ;
-    if (price > amount) then failwith("Not enough money") else skip ;
+    if (price > amount) then fail "Not enough money" else skip ;
     // Administrative procedure
     const operations : list(operation) = nil ;
     // Increase quantity