from source-code CLISP-2.38

hai folks

i was browsing through the source-code of CLISP 2.38, in the file named
"LOOP.lisp" i came across the following function:

(defun destructure-vars (pattern)
(let ((vars '()))
(labels ((accumulate (pattern)
(cond ((null pattern))
((atom pattern) (push pattern vars))
(t
(accumulate (car pattern))
(accumulate (cdr pattern))))))
(accumulate pattern))
(nreverse vars)))

;; OUTPUT
(destructure-vars '(1 2 3 4)) ==> '(1 2 3 4)
(destructure-vars '(1 (((2))) (((3)) 4))) ==> '(1 2 3 4)

ok i got it this function destructures the elements of a tree into a
single list, BUT, then i took out "accumulate" from the "labels" and
tried it as a stand-alone function.


(defun accumulate (pattern)
(let ((vars '()))
(cond ((null pattern))
((atom pattern) (push pattern vars))
(t (accumulate (car pattern))
(accumulate (cdr pattern))))
(nreverse vars)))


;; OUTPUT

(accumulate '(1 2 3 4)) ==> NIL
(accumulate '(1 (((2))) (((3)) 4))) ==> NIL

why it does not produce '(1 2 3 4) even though it's same (only "labels"
is not here)

why two same functions are producing different outputs?

how can i make 2nd one to produce same output as 1st one. i have Debian
"Sarge" running with CLISP - 2.33.2. (i also have SBCL 0.9.11)

thanks

-- arnuld

.

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