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;; extract index number given a header/data structure
(define (db:get-index-by-header header field)
(list-index (lambda (x)(equal? x field)) header))
;; look up values in a header/data structure
(define (db:get-value-by-header row header field)
(let ((len (vector-length row)))
(debug:print 0 *default-log-port* "WARNING: attempt to read non-existant field, row="
row " header=" header " field=" field ", exn=" exn)
#f)
(if (>= n len)
#f
(vector-ref row n)))
(if (null? tal) #f (loop (car tal)(cdr tal)(+ n 1))))))))
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;; extract index number given a header/data structure
(define (db:get-index-by-header header field)
(list-index (lambda (x)(equal? x field)) header))
;; look up values in a header/data structure
(define (db:get-value-by-header row header field)
(let ((len (if (vector? row)
(vector-length row)
0)))
(if (or (null? header) (not row))
#f
(let loop ((hed (car header))
(tal (cdr header))
(n 0))
(if (equal? hed field)
(handle-exceptions
exn
(begin
(debug:print 4 *default-log-port* "WARNING: attempt to read non-existant field, row="
row " header=" header " field=" field ", exn=" exn)
#f)
(if (>= n len)
#f
(vector-ref row n)))
(if (null? tal) #f (loop (car tal)(cdr tal)(+ n 1))))))))
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