push 4.31 upward compat

4.31-test-inputs.rkt

@@ -0,0 +1,35 @@
+#lang racket
+(define (unless pred con alt)(if pred alt con))
+(unless (> 10 5) (/ 1 0) 5)
+(define (unless pred (con lazy) alt)(if pred alt con))
+(unless (> 10 5) (/ 1 0) 5)
+(define (unless pred (con lazy-memo) alt)(if pred alt con))
+(unless (> 10 5) (/ 1 0) 5)
+(define (fib (n lazy-memo))
+  (let fib-iter (((a lazy-memo) 1) ((b lazy-memo) 0) (count n))
+    (if (= count 0)
+        b
+        (fib-iter (+ a b) 
+                  a 
+                  (- count 1)))))
+
+(define (fib n)
+  (if (= n 1)
+      0
+      (if (= n 2)
+          1
+          (+ (fib (- n 1)) (fib (- n 2))))))
+
+(define (fib (n lazy))
+  (if (= n 1)
+      0
+      (if (= n 2)
+          1
+          (+ (fib (- n 1)) (fib (- n 2))))))
+
+(define (fib (n lazy-memo))
+  (if (= n 1)
+      0
+      (if (= n 2)
+          1
+          (+ (fib (- n 1)) (fib (- n 2))))))