diff --git a/vm/tests/t28.scm b/vm/tests/t28.scm
new file mode 100644
index 0000000..9532bf0
--- /dev/null
+++ b/vm/tests/t28.scm
@@ -0,0 +1,17 @@
+;; -*- Mode: Irken -*-
+
+(define x (:thing 1 2 #\A))
+(define y (:other "testing"))
+
+(define myfun
+  (:thing _ two _) -> two
+  (:other _)       -> 19
+  )
+
+(:zorb
+ (myfun x)
+ (myfun y)
+ (myfun (:thing 7 12 #\X))
+ )
+
+
diff --git a/vm/tests/t29.scm b/vm/tests/t29.scm
new file mode 100644
index 0000000..c7af520
--- /dev/null
+++ b/vm/tests/t29.scm
@@ -0,0 +1,15 @@
+;; -*- Mode: Irken -*-
+
+(include "lib/core.scm")
+
+(define thing1 {a=1 b=#\b c="c"})
+(define thing2 {c="hey" b=#\b a=12})
+
+(set! thing2.c "there")
+(set! thing1.a 34)
+
+(print thing1)
+(print thing2)
+(print thing1.a)
+(print thing2.c)
+
diff --git a/vm/tests/t30.scm b/vm/tests/t30.scm
new file mode 100644
index 0000000..11b7140
--- /dev/null
+++ b/vm/tests/t30.scm
@@ -0,0 +1,23 @@
+;; -*- Mode: Irken -*-
+
+(include "lib/core.scm")
+
+;; test op_rset.
+
+(define (^fun1 p)
+  (set! p.y 1001)
+  (+ p.x 10)
+  )
+
+(let ((thing1 {a=0 x=1 y=2 b="what?"})
+      (thing2 {x=3 y=4 z=7}))
+  (set! thing1.x 27)
+  (set! thing2.x 19)
+  (print (^fun1 thing1))
+  (print (^fun1 thing2))
+  (print thing1)
+  (print thing2)
+  )
+
+
+  
diff --git a/vm/tests/t_samefringe.scm b/vm/tests/t_samefringe.scm
new file mode 100644
index 0000000..e7586bb
--- /dev/null
+++ b/vm/tests/t_samefringe.scm
@@ -0,0 +1,43 @@
+;; -*- Mode: Irken -*-
+
+(include "lib/core.scm")
+
+(datatype btree
+  (:node (btree 'a) (btree 'a))
+  (:leaf 'a))
+
+(defmacro btree/make
+  (btree/make (l r)) -> (btree:node (btree/make l) (btree/make r))
+  (btree/make x)     -> (btree:leaf x))
+
+(define t0 (literal (btree/make ((0 ((1 (2 (3 4))) 5)) (((6 7) ((8 (9 10)) 11)) ((12 (((13 14) 15) (16 17))) (18 19)))))))
+(define t1 (literal (btree/make (((0 ((1 2) 3)) (((4 5) (((6 7) 8) (9 10))) ((11 ((12 13) 14)) ((15 (16 17)) 18)))) 19))))
+(define t2 (literal (btree/make (((0 ((1 2) 3)) (((4 5) (((6 7) 8) (9 10))) ((88 ((12 13) 14)) ((15 (16 17)) 18)))) 19))))
+
+(define btree/inorder
+  p (btree:leaf x)   -> (begin (p x) #u)
+  p (btree:node l r) -> (begin (btree/inorder p l) (btree/inorder p r) #u))
+
+(define (btree/make-generator t)
+  (make-generator
+   (lambda (consumer)
+     (btree/inorder
+      (lambda (x) (consumer (maybe:yes x)))
+      t)
+     (forever (consumer (maybe:no))))))
+
+(define (same-fringe t0 t1 =)
+  (let ((g0 (btree/make-generator t0))
+	(g1 (btree/make-generator t1)))
+    (let loop ((m0 (g0)) (m1 (g1)))
+      (match m0 m1 with
+	(maybe:yes v0) (maybe:yes v1)
+	-> (if (= v0 v1)
+	       (loop (g0) (g1))
+	       (print "NOT equal"))
+	(maybe:no) (maybe:no)
+	-> (print "equal")
+	_ _ -> (print "unequal size")))))
+
+(same-fringe t0 t1 =)
+(same-fringe t0 t2 =)