diff --git a/track.cpp b/track.cpp
index a2c39de..a3a2d95 100644
--- a/track.cpp
+++ b/track.cpp
@@ -1,3 +1,4 @@
+#include <cassert>
 #include <iostream>
 #include <ostream>
 // requires C++23 to compile
@@ -17,16 +18,22 @@ public:
     ret.counter--;
     return ret;
   }
-  friend std::ostream &operator<<(std::ostream &lhs, A const &rhs) {
-    lhs << rhs.counter;
-    return lhs;
-  }
+  // friend std::ostream &operator<<(std::ostream &lhs, A const &rhs) {
+  //   lhs << rhs.counter;
+  //   return lhs;
+  // }
+  operator long long() { return counter; }
 };
 
 int main(void) {
   A a;
-  std::cout << a[] << std::endl;
-  std::cout << a[]() << std::endl;
-  std::cout << a[]()() << std::endl;
+  assert(a == 0);
+  assert(a[] == -1);
+  assert(a[]() == 0);
+  assert(a[]()() == 1);
+  int i = a;
+  assert(i == 0);
+  i = a()()();
+  assert(i == 3);
   return 0;
 }