diff --git a/src/sail_json_backend/json.ml b/src/sail_json_backend/json.ml
index f2cf8c076..659a62ed5 100644
--- a/src/sail_json_backend/json.ml
+++ b/src/sail_json_backend/json.ml
@@ -245,13 +245,18 @@ let extract_operands k regex components =
     | hd :: tl ->
         if Str.string_match regex hd 0 then (
           let operand = Str.matched_group 1 hd in
+          let trimmed =
+            try
+              let comma_index = String.index operand ',' in
+              debug_print ("Operand before trimming: " ^ operand);
+              let trimmed_operand = String.sub operand 0 comma_index in
+              debug_print ("Final trimmed operand: " ^ trimmed_operand);
+              trimmed_operand
+            with Not_found -> operand
+          in
           try
-            let comma_index = String.index operand ',' in
-            debug_print ("Operand before trimming: " ^ operand);
-            let trimmed = String.sub operand 0 comma_index in
-            debug_print ("Final trimmed operand: " ^ trimmed);
             let inputl = Hashtbl.find inputs k in
-            if List.mem trimmed inputl then aux (trimmed :: acc) tl else aux acc tl
+            if List.mem operand inputl || List.mem trimmed inputl then aux (trimmed :: acc) tl else aux acc tl
           with Not_found -> aux (operand :: acc) tl
         )
         else aux acc tl