TAILP

[jscl.git] / src / list.lisp

diff --git a/src/list.lisp b/src/list.lisp
index 64c03c9..173dedf 100644 (file)
--- a/src/list.lisp
+++ b/src/list.lisp
@@ -29,7 +29,7 @@
       t
       (if (consp x)
           nil
       t
       (if (consp x)
           nil

-          (error "type-error"))))
+          (error "The value `~S' is not a type list." x))))

 
 (defun car (x)
   "Return the CAR part of a cons, or NIL if X is null."
 
 (defun car (x)
   "Return the CAR part of a cons, or NIL if X is null."

@@ -37,11 +37,17 @@
 
 (defun cdr (x) (cdr x))
 
 
 (defun cdr (x) (cdr x))
 

-(defun first (x) (car x))
-(defun second (x) (cadr x))
-(defun third (x) (caddr x))
-(defun fourth (x) (cadddr x))
-(defun rest (x) (cdr x))
+(defun first   (x) (car    x))
+(defun second  (x) (cadr   x))
+(defun third   (x) (caddr  x))
+(defun fourth  (x) (cadddr x))
+(defun fifth   (x) (car    (cddddr x)))
+(defun sixth   (x) (cadr   (cddddr x)))
+(defun seventh (x) (caddr  (cddddr x)))
+(defun eighth  (x) (cadddr (cddddr x)))
+(defun ninth   (x) (car  (cddddr (cddddr x))))
+(defun tenth   (x) (cadr (cddddr (cddddr x))))
+(defun rest    (x) (cdr x))

 
 (defun list (&rest args)
   args)
 
 (defun list (&rest args)
   args)

@@ -62,7 +68,6 @@
 (defun nth (n list)
   (car (nthcdr n list)))
 
 (defun nth (n list)
   (car (nthcdr n list)))
 

-;;; The rest of the C[AD]*R functions; only a few were defined in boot.lisp

 (defun caar (x) (car (car x)))
 (defun cadr (x) (car (cdr x)))
 (defun cdar (x) (cdr (car x)))
 (defun caar (x) (car (car x)))
 (defun cadr (x) (car (cdr x)))
 (defun cdar (x) (cdr (car x)))

@@ -104,6 +109,19 @@
           (copy-tree (cdr tree)))
     tree))
 
           (copy-tree (cdr tree)))
     tree))
 

+(defun tree-equal (tree1 tree2 &key (test #'eql))
+  (if (atom tree1)
+    (and (atom tree2) (funcall test tree1 tree2))
+    (and (consp tree2)
+         (tree-equal (car tree1) (car tree2) :test test)
+         (tree-equal (cdr tree1) (cdr tree2) :test test))))
+
+(defun tailp (object list)
+  (do ((tail list (cdr tail)))
+    ((atom tail) (eq object tail))
+    (when (eql tail object)
+      (return-from tailp t))))
+

 (defun subst (new old tree &key (key #'identity) (test #'eql))
   (cond 
     ((funcall test (funcall key tree) (funcall key old))
 (defun subst (new old tree &key (key #'identity) (test #'eql))
   (cond 
     ((funcall test (funcall key tree) (funcall key old))