Taking values from a Ruby array of hashes

Question

I have an array of hashes:

a = [{"Key1"=>"Value1", "Key2"=>"Value2"}, 
     {"Key1"=>"Value3", "Key2"=>"Value4"},
     {"Key1"=>"Value5", "Key2"=>"Value6"}]

Basically I am trying to get an output with only values and not any keys. Something like this

['Value1', 'Value2', 'Value3', 'Value4', 'Value5', 'Value6']

Here is the code which I tried. As key1 and key2 are the same, I stored both the keys in an array....

k = ["key1", "key2"]
for i in 0..a.length  
  k.each do |key_to_delete| 
    a[i].delete key_to_delete unless a[i].nil?
  end 
end

However, this removes all values and I get an empty array. Any help is appreciated.

Actually you don't have a ruby hash in a, you have an array of hashes in a. — Bret Weinraub
– Bret Weinraub, Commented May 27, 2016 at 8:10
do you want an array of arrays, or just a single array of all the values? — x6iae
– x6iae, Commented May 27, 2016 at 8:13
Maybe you want this? [["Value1", "Value2"], ["Value3", "Value4"], ["Value5", "Value6"]] (Just modify Ilya's answer to use map instead of flat_map) — libcthorne
– libcthorne, Commented May 27, 2016 at 8:14

Ilya · Accepted Answer · 2016-05-27 08:20:48Z

5

You can use Enumerable#flat_map and fetch values from each hash:

a.flat_map(&:values)
=> ["Value1", "Value2", "Value3", "Value4", "Value5", "Value6"]

This is an answer on the original question.

answered May 27, 2016 at 8:08

Ilya

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4 Comments

Or even more shorter: a.flat_map(&:values)

Perfect and this is the output I wanted. Thanks a lot for your lightning response :)

@TGR this is basically the output you had in your original question, why did you change it?

@Stefan I was little confused. Apols for confusion. I am perfectly fine with llya & Sergil's output