You might find this function helpful (from the implementation of in-query):
(define (in-list/vector->values vs)
(make-do-sequence
(lambda ()
(values (lambda (p) (vector->values (car p)))
cdr
vs
pair? #f #f))))
Ryan
On 05/04/2016 09:46 AM, Denis Fadeev wrote:
That's better than vector-ref:
,@(for/list (((some-string some-list-of-vectors) (in-query ... #:group ...)
`(h1 ,(~a some-string))
,@(for/list (((some-vector) some-list-of-vectors))
(match-define (vector some-string2 some-string3) some-vector)
`(p ,(~a some-string2)
I would obviously preferred something like:
,@(for/list (((some-string some-list-of-vectors) (in-query ... #:group ...)
`(h1 ,(~a some-string))
,@(for/list (((some-string2 some-string3) (MAGIC!
some-list-of-vectors)))
`(p ,(~a some-string2)
среда, 4 мая 2016 г., 13:00:22 UTC+5 пользователь Denis Fadeev написал:
Hi,
I'm querying a DB using in-query with #:group. For every iteration it returns
multiple values, which i bind to some-string and some-list-of-vectors. Next, I
iterate through some-list-of-vectors, but some-list-of-vectors is no sequence,
so I can't bind multiple values like I did in the first for/list.
,@(for/list (((some-string some-list-of-vectors) (in-query ... #:group ...)
`(h1 ,(~a some-string))
,@(for/list (((some-string2 some-string3) some-list-of-vectors))
`(p ,(~a some-string2)
How can I bind values in the second for/list the same way I did in the first
for list. Can I convert some-list-of-vectors to a sequence? I just really like
the concise way of binding multiple values inside for/list. Of course, i can
vector-ref in the second for/list, but that's not as nice. I'm using it to
populate an xexpr. Maybe, there is a better way to do it?
Any help would be greatly appreciated!
Denis.
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