Detele repeated in a list

[B. Pym]

(defun rem-duplicates (list)
(loop for (first . rest) on (append list list)
unless (member first (reverse rest) :test #'equal)
collect first))

Gauche Scheme

(define (rem-dups lst)
(fold
(lambda (x accum) (if (member x accum) accum (cons x accum)))
'()
lst))

(rem-dups '(0 2 3 4 (8 7) 3 2 0 (8 7)))
===>
(4 3 2 0 (8 7))

[B. Pym]

Post by B. Pym

(defun rem-duplicates (list)
(loop for (first . rest) on (append list list)
unless (member first (reverse rest) :test #'equal)
collect first))

Gauche Scheme
(define (rem-dups lst)
(fold
(lambda (x accum) (if (member x accum) accum (cons x accum)))
'()
lst))
(rem-dups '(0 2 3 4 (8 7) 3 2 0 (8 7)))
===>
(4 3 2 0 (8 7))

Actual result:

((8 7) 4 3 2 0)

[HenHanna]

Post by B. Pym

Post by B. Pym

(defun rem-duplicates (list)
(loop for (first . rest) on (append list list)
unless (member first (reverse rest) :test #'equal)
collect first))

Gauche Scheme
(define (rem-dups lst)
(fold
(lambda (x accum) (if (member x accum) accum (cons x accum)))
'()
lst))
(rem-dups '(0 2 3 4 (8 7) 3 2 0 (8 7)))
===>
(4 3 2 0 (8 7))

((8 7) 4 3 2 0)

Gauche doesn't have RemDup built in?

[HenHanna]

Post by B. Pym

Post by B. Pym

(defun rem-duplicates (list)
    (loop for (first . rest) on (append list list)
          unless (member first (reverse rest) :test #'equal)
          collect first))

Gauche Scheme
(define (rem-dups lst)
   (fold
     (lambda (x accum) (if (member x accum) accum (cons x accum)))
     '()
     lst))
(rem-dups '(0 2 3 4 (8 7) 3 2 0 (8 7)))
   ===>
(4 3 2 0 (8 7))

((8 7) 4 3 2 0)

Gauche doesn't have RemDup  built in?

i remember that ... Rember was one of the 1st
exercises in intro to Lisp

Maybe there was a naming convention that suggested
that ... Delete is destructive and Remove is not.


_________________________________________________________

delete x list :optional elt= [Function]
delete! x list :optional elt= [Function]

[R7RS list] Equivalent to
(remove (lambda (y) (elt= x y)) list)
(remove! (lambda (y) (elt= x y)) list)

The comparison procedure, elt=, defaults to equal?.


delete-duplicates list :optional elt= [Function]

[B. Pym]

Post by B. Pym

Post by B. Pym

(defun rem-duplicates (list)
(loop for (first . rest) on (append list list)
unless (member first (reverse rest) :test #'equal)
collect first))

Gauche Scheme
(define (rem-dups lst)
(fold
(lambda (x accum) (if (member x accum) accum (cons x accum)))
'()
lst))
(rem-dups '(0 2 3 4 (8 7) 3 2 0 (8 7)))
===>
(4 3 2 0 (8 7))

((8 7) 4 3 2 0)

newLISP

(define (rem-dups lst)
;; Using "apply" for "reduce" or "fold".
(apply
(fn (accum x) (if (member x accum) accum (push x accum -1)))
(cons '() lst)
2))

(rem-dups '(0 2 3 4 (8 7) 3 2 0 (8 7)))

(0 2 3 4 (8 7))