diff --git a/panda/src/collide/collisionHandlerQueue.h b/panda/src/collide/collisionHandlerQueue.h
index 5f39a04a6b..f0857c09bf 100644
--- a/panda/src/collide/collisionHandlerQueue.h
+++ b/panda/src/collide/collisionHandlerQueue.h
@@ -19,7 +19,7 @@
 #ifndef COLLISIONHANDLERQUEUE_H
 #define COLLISIONHANDLERQUEUE_H
 
-#include <pandabase.h>
+#include "pandabase.h"
 
 #include "collisionHandler.h"
 #include "collisionEntry.h"
diff --git a/panda/src/collide/collisionTraverser.I b/panda/src/collide/collisionTraverser.I
index 80cea3eff9..258fff744f 100644
--- a/panda/src/collide/collisionTraverser.I
+++ b/panda/src/collide/collisionTraverser.I
@@ -83,4 +83,15 @@ clear_recorder() {
   set_recorder((CollisionRecorder *)NULL);
 }
 
+////////////////////////////////////////////////////////////////////
+//     Function: CollisionTraverser::ls
+//       Access: Published
+//  Description: Shortcut for write().  This is handy for interactive
+//               debugging.
+////////////////////////////////////////////////////////////////////
+INLINE void CollisionTraverser::
+ls() const {
+  write(nout, 0);
+}
+
 #endif  // DO_COLLISION_RECORDING
diff --git a/panda/src/collide/collisionTraverser.h b/panda/src/collide/collisionTraverser.h
index 994019eb55..a041ed4585 100644
--- a/panda/src/collide/collisionTraverser.h
+++ b/panda/src/collide/collisionTraverser.h
@@ -80,6 +80,7 @@ PUBLISHED:
 #endif  // DO_COLLISION_RECORDING
 
   void output(ostream &out) const;
+  INLINE void ls() const;
   void write(ostream &out, int indent_level) const;
 
 private: