add missing list functions

piclib/built-in.scm

@@ -29,6 +29,14 @@
 	  (list? (cdr obj))
 	  #f)))
 
+(define (make-list k . args)
+  (if (null? args)
+      (make-list k #f)
+      (if (zero? k)
+	  '()
+	  (cons (car args)
+		(make-list (- k 1) (car args))))))
+
 (define (length list)
   (if (null? list)
       0
@@ -40,6 +48,14 @@
       (cons (car xs)
 	    (append (cdr xs) ys))))
 
+(define (reverse list . args)
+  (if (null? args)
+      (reverse list '())
+      (if (null? list)
+	  (car args)
+	  (reverse (cdr list)
+		   (cons (car list) (car args))))))
+
 (define (list-tail list k)
   (if (zero? k)
       list
@@ -47,3 +63,12 @@
 
 (define (list-ref list k)
   (car (list-tail list k)))
+
+(define (list-set! list k obj)
+  (set-car! (list-tail list k) obj))
+
+(define (list-copy obj)
+  (if (null? obj)
+      obj
+      (cons (car obj)
+	    (list-copy (cdr obj)))))