Fix: fix a bug occuring when reading RIF with no input or no output

src/rifIO.ml

-(* Time-stamp: <modified the 23/04/2019 (at 11:10) by Erwan Jahier> *)
+(* Time-stamp: <modified the 10/07/2019 (at 17:41) by Erwan Jahier> *)
 (*-----------------------------------------------------------------------
 ** This file may only be copied under the terms of the CeCILL
 ** Public License
@@ -105,9 +105,9 @@ let rec (read_until_pragma_end :?debug:(bool) -> in_channel -> out_channel optio
 let rec (read_interface : ?debug:(bool) -> ?label:(string) -> in_channel ->
          out_channel option -> vntl * vntl) =
   fun ?(debug=false) ?(label="") ic oc -> 
-    let rec loop ins outs =
-      if ins <> [] && outs <> [] then ins, outs else
-      let line = read_line debug label ic oc in
+    let rec loop ins outs in_done out_done =
+      if in_done && out_done then ins, outs else
+        let line =  read_line debug label ic oc in
         try
           if (Str.string_match (Str.regexp "#end") line 0) || line = "q" || line = "bye"
           then (
@@ -120,35 +120,35 @@ let rec (read_interface : ?debug:(bool) -> ?label:(string) -> in_channel ->
             let str = strsub line 7 (String.length line - 7) in
             let l = Str.split (Str.regexp " ") str in
             let l = List.filter (fun str -> str <> "") l in
-              loop (List.map to_pair l) outs
+              loop (List.map to_pair l) outs true out_done
                 
           else if Str.string_match (Str.regexp "@#inputs") line 0 then          
             let str = strsub line 8 (String.length line - 8) in
             let str = read_until_pragma_end ~debug:debug ic oc str in
             let l = Str.split (Str.regexp " ") str in
             let l = List.filter (fun str -> str <> "") l in
-              loop (List.map to_pair l) outs
+              loop (List.map to_pair l) outs true out_done
                 
           else if Str.string_match (Str.regexp "#outputs") line 0 then
             let str = strsub line 8 (String.length line - 8) in
             let l = Str.split (Str.regexp " ") str in
             let l = List.filter (fun str -> str <> "") l in
-              loop ins (List.map to_pair l)
+              loop ins (List.map to_pair l) in_done true
                 
           else if Str.string_match (Str.regexp "@#outputs") line 0 then          
             let str = strsub line 9 (String.length line - 9) in
             let str = read_until_pragma_end ~debug:debug ic oc str in
             let l = Str.split (Str.regexp " ") str in
             let l = List.filter (fun str -> str <> "") l in
-              loop ins (List.map to_pair l)
+              loop ins (List.map to_pair l) in_done true
           else
-            loop ins outs
+            loop ins outs in_done out_done
         with e -> 
           print_string ("#" ^line ^"\n");
           flush stdout;
           raise e
     in
-      loop [] []
+      loop [] [] false false
 
 
 (* exported *)