Ruby filtering array of hash

Question

I have the following array of arguments that has a hash with the args keys and their relevant passed values:

args_array = [{:collection=>["abe", "<mus>", "hest"], :include_blank=>true, :required=>true}]

I need to filter this hash to just get only some keys (like :include_blank and :required) in this example, with their relevant values like so:

filtered_args_hash = {:include_blank=>true, :required=>true}

So the collection arg is excluded, and just the include_blank, and required in which I specified are the ones returned.

Update:

Here is a keys array of symbols in which I need to filter according to them:

filter_keys = %i(include_blank required)

How I can do that?

Yes, keys = %i(include_blank required)

Wazery
– Wazery

2015-07-01 13:48:04 +00:00
Commented Jul 1, 2015 at 13:48 — Wazery
– Wazery, Commented Jul 1, 2015 at 13:48

Yu Hao · Accepted Answer · 2015-07-01 14:04:45Z

2

One way is to use Hash#keep_if:

args_array[0].dup.keep_if {|k| filter_keys.include? k}
# => {:include_blank=>true, :required=>true}

_{Note that .dup is here to prevent args_array from being modified, don't use it if you do want args_array to be updated.}

edited Jul 1, 2015 at 14:04

answered Jul 1, 2015 at 13:54

Yu Hao

123k50 gold badges252 silver badges305 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

cremno Over a year ago

That modifies args_array[0] though. If I understand the question correctly, that behavior doesn't seem to be okay (maybe it is). Hash#select can be used in this case.

Rubyrider · Accepted Answer · 2015-07-01 13:52:54Z

1

The following should do solve your problem:

 args_array.collect {|a| a if a[:include_blank] == true && a[:required=>true] == true }.compact

or

dup_list = args_array.dup
dup_list.delete_if {|a| !(a[:include_blank] == true && a[:required=>true] == true) }

answered Jul 1, 2015 at 13:52

Rubyrider

3,6071 gold badge30 silver badges34 bronze badges

2 Comments

Wazery Over a year ago

But I need the include_blank and required returned with their values, whether they are true or false or whatever.

Rubyrider Over a year ago

So you want to group them by include_blank and required ?

Aleksei Matiushkin · Accepted Answer · 2015-07-01 14:38:46Z

1

args_array.map do |elem| 
  elem.select do |k, _| 
    %i(include_blank required).include? k
  end
end

answered Jul 1, 2015 at 14:38

Aleksei Matiushkin

121k12 gold badges109 silver badges173 bronze badges

Comments

Doguita · Accepted Answer · 2015-07-01 16:56:09Z

1

You tagged as Rails so you can use Hash#slice:

args_array[0].slice *filter_keys
# => {:include_blank=>true, :required=>true}

answered Jul 1, 2015 at 16:56

Doguita

15.8k3 gold badges29 silver badges37 bronze badges

Collectives™ on Stack Overflow

Ruby filtering array of hash

4 Answers 4

1 Comment

2 Comments

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

4 Answers 4

1 Comment

2 Comments

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related