--- a/src/value.c	Tue Sep 03 12:16:44 2019 +0200
+++ b/src/value.c	Tue Sep 03 12:17:19 2019 +0200
@@ -89,6 +89,21 @@
     return ref;
 }
 
+bool yref_eq(yref_t* a, yref_t* b) {
+    if (yref_type(a) != yref_type(b)) return false;
+    YREF_TYPE t = yref_type(a);
+    switch (t) {
+        case YREF_SYM:
+            return 0 == ystr_cmp(&a->ref.sym, &b->ref.sym);
+        case YREF_ID:
+            return a->ref.id == b->ref.id;
+        case YREF_STACK:
+            return a->ref.cix == b->ref.cix;
+        default:
+            return false;
+    }
+}
+
 uint64_t yref_cix(yref_t* ref) { return ref->ref.cix ^ YVALUE_CIX_MARKER; }
 
 yref_t yref_clone(yref_t* ref) {
@@ -274,6 +289,5 @@
     }
     hdestroy_r(&yvalue_name_table);
     yvec_destroy(&yvalue_table);
-    fprintf(stderr, "freed %llu values\n", freed);
 }
 

--- a/src/value.h	Tue Sep 03 12:16:44 2019 +0200
+++ b/src/value.h	Tue Sep 03 12:17:19 2019 +0200
@@ -83,6 +83,11 @@
 uint64_t yref_cix(yref_t* ref);
 
 /**
+ * Return true if the references are identical.
+ */
+bool yref_eq(yref_t* a, yref_t* b);
+
+/**
  * Create a debug description of ref.
  */
 ystr_t yref_debug(yref_t* ref);