obscure problem

[David Pirotte]

Hello,

given the following defs:

(define (db-utils/build-db-class-slots table-attrs)
  (let ((slots '(db-oid))
        (slot-defs '((db-oid #:accessor db-oid
                             #:init-keyword #:db-oid
                             #:init-value #f))))
    (for-each (lambda (table-attr)
                (let* ((attr-name (cadr table-attr))
                       (slot (string->symbol attr-name))
                       (slot-kw (symbol->keyword slot)))
                  (set! slots (cons slot slots))
                  (set! slot-defs (cons `(,slot #:accessor ,slot
                                                #:init-keyword ,slot-kw
                                                #:init-value #f)
                                        slot-defs))))
              table-attrs)
    (values (reverse! slots)
            (reverse! slot-defs))
    ))

(define attrs '(("1" "reference" "text") ("2" "nom" "text") ("3" "zone" "text") 
("4" "pos_x" "int4") ("5" "pos_y" "int4") ("6"
"ref_projet" "text") ("7" "img_nb" "int2")))

I can not point out why the first call does produce the expected result:

guile> (db-utils/build-db-class-slots attrs)
#<values values: ((db-oid reference nom zone pos_x pos_y ref_projet img_nb) 
((db-oid #:accessor db-oid #:init-keyword #:db-oid
#:init-value #f) (reference #:accessor reference #:init-keyword #:reference 
#:init-value #f) (nom #:accessor nom #:init-keyword
#:nom #:init-value #f) (zone #:accessor zone #:init-keyword #:zone #:init-value 
#f) (pos_x #:accessor pos_x #:init-keyword #:pos_x
#:init-value #f) (pos_y #:accessor pos_y #:init-keyword #:pos_y #:init-value 
#f) (ref_projet #:accessor ref_projet #:init-keyword
#:ref_projet #:init-value #f) (img_nb #:accessor img_nb #:init-keyword #:img_nb 
#:init-value #f)))>
guile> 



BUT, the second and subsequent calls not: (just to make sure that attrs
remained as defined at first)

guile> attrs
(("1" "reference" "text") ("2" "nom" "text") ("3" "zone" "text") ("4" "pos_x" 
"int4") ("5" "pos_y" "int4") ("6" "ref_projet" "text")
("7" "img_nb" "int2"))
guile> 

guile> (db-utils/build-db-class-slots attrs)
#<values values: ((img_nb ref_projet pos_y pos_x zone nom reference db-oid 
reference nom zone pos_x pos_y ref_projet img_nb)
((img_nb #:accessor img_nb #:init-keyword #:img_nb #:init-value #f) (ref_projet 
#:accessor ref_projet #:init-keyword #:ref_projet
#:init-value #f) (pos_y #:accessor pos_y #:init-keyword #:pos_y #:init-value 
#f) (pos_x #:accessor pos_x #:init-keyword #:pos_x
#:init-value #f) (zone #:accessor zone #:init-keyword #:zone #:init-value #f) 
(nom #:accessor nom #:init-keyword #:nom #:init-value
#f) (reference #:accessor reference #:init-keyword #:reference #:init-value #f) 
(db-oid #:accessor db-oid #:init-keyword #:db-oid
#:init-value #f) (reference #:accessor reference #:init-keyword #:reference 
#:init-value #f) (nom #:accessor nom #:init-keyword
#:nom #:init-value #f) (zone #:accessor zone #:init-keyword #:zone #:init-value 
#f) (pos_x #:accessor pos_x #:init-keyword #:pos_x
#:init-value #f) (pos_y #:accessor pos_y #:init-keyword #:pos_y #:init-value 
#f) (ref_projet #:accessor ref_projet #:init-keyword
#:ref_projet #:init-value #f) (img_nb #:accessor img_nb #:init-keyword #:img_nb 
#:init-value #f)))>
guile> 

??? further calls would always produce the latest results, doubling 

HOWEVER, if I change both calls to 'reverse!' and use 'reverse' instead, it 
does work,
is this the expected behavior?

thanks
david