Replace mcons with build-in mlist function

Author: ramsayleung

chapter3/1d-table.rkt

@@ -1,7 +1,8 @@
 #lang racket
+(require compatibility/mlist)
 
 (define (make-table)
-  (mcons '*table* '()))
+  (mlist '*table*))
 
 (define (assoc key records)
   (cond ((null? records) false)

chapter3/2d-table.rkt

@@ -1,5 +1,6 @@
 #lang racket
 (require "1d-table.rkt")
+(require compatibility/mlist)
 
 (define (make-table)
   (let ((local-table (mcons '*table* '())))
@@ -20,10 +21,9 @@
                   (set-mcdr! record value)
                   (set-mcdr! subtable (mcons (mcons key-2 value)
                                              (mcdr subtable)))))
-            (set-mcdr! local-table (mcons
-                                    (mcons key-1
-                                           (mcons (mcons key-2 value) '()))
-                                    (mcdr local-table)))))
+            (set-mcdr! local-table (mcons (mlist key-1
+                                                 (mcons key-2 value))
+                                          (mcdr local-table)))))
       'ok)
     (define (dispatch m)
       (cond ((eq? m 'lookup-proc) lookup)

chapter3/exercise3-25.rkt

@@ -1,9 +1,10 @@
 #lang racket
+(require compatibility/mlist)
 
 ;;; 实现与一维数组一致，差别在于 key 的表达方式，与原来使用 'a 的字符
 ;;; 变量作为 key 不同，现在使用 '(a b) 列表作为 key
 (define (make-table)
-  (let ((local-table (mcons '*table* '())))
+  (let ((local-table (mlist '*table*)))
     (define (assoc key records)
       (cond ((null? records) false)
             ((equal? key (mcar (mcar records)))