Index: src/natools-s_expressions-printers-pretty.adb
==================================================================
--- src/natools-s_expressions-printers-pretty.adb
+++ src/natools-s_expressions-printers-pretty.adb
@@ -564,10 +564,11 @@
          Result : in out Atom;
          Pos : in Offset);
 
       Size : Count;
       Last_Non_NL : Offset := Data'Last;
+      Expected_Cursor : Screen_Offset := Output.Cursor;
 
       procedure Escape
         (Value : in Octet;
          Result : in out Atom;
          Pos : in Offset) is
@@ -587,22 +588,18 @@
                   Result (Pos + 2),
                   Result (Pos + 3));
          end case;
       end Escape;
    begin
-      declare
-         Discarded_Cursor : Screen_Offset := Output.Cursor;
-      begin
-         Quoted_Lengths
-           (Data,
-            Output.Param.Char_Encoding,
-            Output.Param.Width,
-            Output.Param.Newline,
-            Single_Line,
-            Size,
-            Discarded_Cursor);
-      end;
+      Quoted_Lengths
+        (Data,
+         Output.Param.Char_Encoding,
+         Output.Param.Width,
+         Output.Param.Newline,
+         Single_Line,
+         Size,
+         Expected_Cursor);
 
       while Last_Non_NL in Data'Range
         and then (Data (Last_Non_NL) = Encodings.CR
                   or Data (Last_Non_NL) = Encodings.LF)
       loop
@@ -756,10 +753,12 @@
          pragma Assert (O = Result'Last);
          Result (O) := Encodings.Quoted_Atom_End;
 
          Write_Raw (Printer'Class (Output), Result);
       end;
+
+      pragma Assert (Output.Cursor = Expected_Cursor);
    end Write_Quoted;
 
 
    procedure Write_Verbatim (Output : in out Printer; Data : in Atom) is
       Length_Image : constant String := Count'Image (Data'Length);