That is exactly the function I was trying to find or write. Thanks! 12.05.2016, 01:04, "Ryan Culpepper" <ry...@ccs.neu.edu>: > 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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