On 08/05/2013 11:30 AM, John Griffin wrote:
Thanks in advance for any advice leading to more succinct hash access.
Had you considered something along the lines of
(define (handier-style data)
(when (@ data 'COMPANY)
(db-exec ... (@ data 'COMPANY))))
?
You might start from
(define (@ base . path)
(match path
['() base]
[(cons (? number? n) rest)
(apply @ (list-ref base n) rest)]
[(cons (? symbol? k) rest)
(apply @ (hash-ref base k) rest)]
[... maybe other things ...]))
to give yourself a not-quite-XPath-like means of projecting JSON values.
Interesting design decisions include: what to do when a list index is
out of range, or a hash key is not present? (Error? Terminate early
returning some kind of "undefined" value?)
Cheers,
Tony
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