Ruby hash to XML: How would I create duplicate keys in a hash for repeated XML xpaths?

Question

I have to create XML that looks something like this:

<?xml version="1.0" ?>
<FirstLevel>
  <Package>
    <Name></Name>
  </Package>
  <Package>
    <Name></Name>
  </Package>
  ...
</FirstLevel>

As you can see, Package shows up multiple times at the same level in the structure.

I know you can't have duplicate keys in a Ruby hash, so I don't know how I would be able to go from a hash to XML when there are duplicate keys. Does anyone have any ideas?

I'm using Hash#to_xml to convert my hash to XML (made available by ActiveSupport I believe).

By the way, I'm using Rails.

Also you can use nokogiri xml to use/access the xml. – Малъ Скрылевъ Jan 10 '14 at 16:59 — Малъ Скрылевъ, Jan 10 '14 at 16:59

score 3 · Accepted Answer · edited May 23 '17 at 10:34

3

Okay I believe I figured it out. You have to use Hash#compare_by_identity. I believe this makes it so that the key lookups are done using object id as opposed to string matches.

I found it in "Ruby Hash with duplicate keys?".

{}.compare_by_identity

    h1 = {}
    h1.compare_by_identity
    h1["a"] = 1
    h1["a"] = 2
    p h1 # => {"a"=>1, "a"=>2}

edited May 23 '17 at 10:34

Community

1
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answered Jan 10 '14 at 16:54

bigpotato

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Ruby hash to XML: How would I create duplicate keys in a hash for repeated XML xpaths?

1 Answers1