Forum: Ruby on Rails nested hash and nil question

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Eecd295cdec2454c66e2015036a39408?d=identicon&s=25 Scott Nj (scottnj)
on 2009-05-12 07:54
(Received via mailing list)
i need to pull out some specific values from a nested hash, but nils
are driving me crazy. in the following example, if address_details,
country, administrative_area, locality OR postal_code are nil i get
"The error occurred while evaluating nil.[]"

zip = placemark['address_details']['country']['administrative_area']
['locality']['postal_code']['postal_code_number']

i tried

unless placemark['address_details']['country']['administrative_area']
['locality']['postal_code']['postal_code_number'].nil?

but if anything above postal_code_number is nil i still get the error.
i could check each level but that is really ugly.

is there a easy way to check if postal_code_number exists?
3be29bee1806b097fc68621eb45f2e37?d=identicon&s=25 Ryan Waldron (rew)
on 2009-05-12 09:02
(Received via mailing list)
What value should 'zip' contain if postal_code_number doesn't exist (or
any
of the keys above it)?

If one of the keys in that long nasty chain are nil, you're going to get
an
exception, but if you know an acceptable default value in case you can't
eval the whole expression, rescue the exception and return what you
want.

If you want it to be an empty string, for instance, you could do:

zip =
placemark['address_details']['country']['administrative_area']['locality']['postal_code']['postal_code_number']
rescue ''
Eecd295cdec2454c66e2015036a39408?d=identicon&s=25 Scott Nj (scottnj)
on 2009-05-12 16:25
(Received via mailing list)
that will work perfect, thanks
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