learning-sicp

commit 46989fdf7512d7d702ac20fc3b5643668052f2ab
parent 628ab61366b9134104882076e95c6b9f3200a431
Author: Yuval Langer <yuval.langer@gmail.com>
Date:   Sun, 16 Apr 2023 12:22:36 +0300

Add exercise 3.15 solution.

Diffstat:
A
sicp/tests/3_15.scm
 | 
78
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

1 file changed, 78 insertions(+), 0 deletions(-)
diff --git a/sicp/tests/3_15.scm b/sicp/tests/3_15.scm
@@ -0,0 +1,78 @@
+(define-library (sicp tests 3_15)
+  (import (scheme base))
+  (import (srfi :64))
+
+  (begin
+    (test-begin "3.15")
+
+    (define (set-to-wow! x)
+      (set-car! (car x) 'wow)
+      x)
+
+    (define x (list 'a 'b))
+    (define z1 (cons x x))
+    (define z2 (cons (list 'a 'b)
+                     (list 'a 'b)))
+    ;;         +---+---+
+    ;; z1: --> | * | * |
+    ;;         +-|-+-|-+
+    ;;           V   V
+    ;;         +---+---+     +---+---+
+    ;;  x: --> | * | *-+---->| * | / |
+    ;;         +-|-+---+     +-|-+---+
+    ;;           V             V
+    ;;         +---+         +---+
+    ;;         | a |         | b |
+    ;;         +---+         +---+
+    ;;
+    ;;         +---+---+     +---+---+    +---+---+
+    ;; z2: --> | * | * +---->| * | *-+--->| * | / |
+    ;;         +-|-+---+     +-|-+---+    +-|-+---+
+    ;;           |             V            V
+    ;;           |           +---+        +---+
+    ;;           |           | a |        | b |
+    ;;           |           +---+        +---+
+    ;;           |             ^            ^
+    ;;           |             |            |
+    ;;           |           +-|-+---+    +-|-+---+
+    ;;           +---------->| * | *-+--->| * | / |
+    ;;                       +---+---+    +---+---+
+    (test-equal '(a b) x)
+    (test-equal '((a b) a b) z1)
+    (test-equal '((a b) a b) z2)
+
+    (set-to-wow! z1)
+    (set-to-wow! z2)
+    ;;         +---+---+
+    ;; z1: --> | * | * |
+    ;;         +-|-+-|-+
+    ;;           V   V
+    ;;         +---+---+     +---+---+
+    ;;  x: --> | * | *-+---->| * | / |
+    ;;         +-|-+---+     +-|-+---+
+    ;;           V             V
+    ;;        +-----+        +---+
+    ;;        | wow |        | b |
+    ;;        +-----+        +---+
+    ;;
+    ;;         +---+---+     +---+---+    +---+---+
+    ;; z2: --> | * | * +---->| * | *-+--->| * | / |
+    ;;         +-|-+---+     +-|-+---+    +-|-+---+
+    ;;           |             V            V
+    ;;           |           +---+        +---+
+    ;;           |           | a |        | b |
+    ;;           |           +---+        +---+
+    ;;           |                          ^
+    ;;           |          +-----+         |
+    ;;           |          | wow |         |
+    ;;           |          +-----+         |
+    ;;           |             ^            |
+    ;;           |             |            |
+    ;;           |           +-|-+---+    +-|-+---+
+    ;;           +---------->| * | *-+--->| * | / |
+    ;;                       +---+---+    +---+---+
+    (test-equal '(wow b) x)
+    (test-equal '((wow b) wow b) z1)
+    (test-equal '((wow b) a b) z2)
+
+    (test-end "3.15")))