From b7e7290d8c9ae6368c60db61efd23194f2608f89 Mon Sep 17 00:00:00 2001
From: Robby <robby@santoslab.org>
Date: Fri, 22 Mar 2024 09:40:30 -0500
Subject: [PATCH] Rewriting system.

---
 .../main/scala/org/sireum/logika/RewritingSystem.scala    | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/shared/src/main/scala/org/sireum/logika/RewritingSystem.scala b/shared/src/main/scala/org/sireum/logika/RewritingSystem.scala
index d61e1196..6892de1b 100644
--- a/shared/src/main/scala/org/sireum/logika/RewritingSystem.scala
+++ b/shared/src/main/scala/org/sireum/logika/RewritingSystem.scala
@@ -1911,11 +1911,9 @@ object RewritingSystem {
         rOpt match {
           case Some(_: AST.CoreExp.Lit) => done = T
           case Some(r) =>
-            val rOpt2 = evalBaseH(r)
-            if (rOpt2.isEmpty) {
-              done = T
-            } else {
-              rOpt = rOpt2
+            evalBaseH(r) match {
+              case rOpt2@Some(r2) if r != r2 => rOpt = rOpt2
+              case _ => done = T
             }
           case _ => done = T
         }