Question

Here is the big hash that I start with (actually its been refined a step or two but this is what I’m starting with at this point.

angel_hash = {"follower_count"=>1369, "name"=>"AngelList", "markets"=>
[{"display_name"=>"Startups", "name"=>"startups", "id"=>448, "tag_type"=>"MarketTag", 
"angellist_url"=>"http://angel.co/startups-1"}, {"display_name"=>"Venture Capital",
 "name"=>"venture capital", "id"=>856, "tag_type"=>"MarketTag", 
"angellist_url"=>"http://angel.co/venture-capital"}], "video_url"=>"", 
"created_at"=>"2011-03-18T00:24:29Z", "updated_at"=>"2012-07-09T14:12:28Z", 
"product_desc"=>"AngelList is a platform for startups to meet investors and talent. ", 
"blog_url"=>"http://blog.angel.co", 
"thumb_url"=>"https://s3.amazonaws.com/photos.angel.co/startups/i/6702-
766d1ce00c99ce9a5cbc19d0c87a436e-thumb_jpg.jpg", "id"=>6702, 
"company_url"=>"http://angel.co", "locations"=>[{"display_name"=>"San Francisco", 
"name"=>"san francisco", "id"=>1692, "tag_type"=>"LocationTag", 
"angellist_url"=>"http://angel.co/san-francisco"}], "community_profile"=>false, "status"=>
{"message"=>"Done Deal: @volunteerspot raises $1.5M 
http://techcrunch.com/2012/06/27/targeting-power-moms-volunteerspot-secures-1-5m-in-   
series-a-from-ff-venture-capital-and-more/ \316\207 20 intros on AngelList \316\207 Funded 
by @ff-venture-capital", "created_at"=>"2012-06-28T20:37:58Z", "id"=>63110},
"twitter_url"=>"http://twitter.com/angellist", "high_concept"=>"A platform for startups", 
"logo_url"=>"https://s3.amazonaws.com/photos.angel.co/startups/i/6702
-766d1ce00c99ce9a5cbc19d0c87a436e-medium_jpg.jpg", 
"angellist_url"=>"http://angel.co/angellist", "screenshots"=>
  [{"thumb"=>"https://s3.amazonaws.com/screenshots.angel.co/98/6702/009cff275fb96709c915c4d4abc9 
43d6-thumb_jpg.jpg", 

"original"=>"https://s3.amazonaws.com/screenshots.angel.co/98/6702/009cff275fb96709c915c4d4abc
943d6-original.jpg"}], "hidden"=>false}

Out of this hash I parsed out some elements, and am doing just fine until I run into the embedded arrays

module SimpleAngel
  class Company

    attr_accessor :followers, :company_name, :markets_array, :date_joined, :locations_array
    attr_accessor :high_concept, :high_concept_long, :thumbnail_logo, :full_size_logo
    attr_accessor :angel_url, :twitter_url, :company_url, :blog_url

    def initialize(angel_hash)
      @followers = angel_hash['follower_count']
      @company_name = angel_hash['name']
      @markets_array = angel_hash['markets']
      @markets_array.each_with_index do |market, i|
      ###This is where I'm stuck. I want to pull out individual elements 
       # from each array AND dynamically assign unique instance variable names for   
       # each separate market in the markets array. Something like @market1_name, 
       # @market1_id, etc.

    end


    @date_joined = angel_hash['created_at']
    @locations_array = angel_hash['locations']
    @high_concept = angel_hash['high_concept']
    @high_concept_long = angel_hash['product_desc']
    @thumbnail_logo = angel_hash['thumb_url']
    @full_size_logo = angel_hash['logo_url']
    @angel_url = angel_hash['angellist_url']
    @twitter_url = angel_hash['twitter_url']
    @company_url = angel_hash['company_url']
    @blog_url = angel_hash['blog_url']
  end

 end
end

Answer 1

Here’s a direct answer to your question: you can define arbitrary instance variable by calling instance_variable_set.

@markets_array.each_with_index do |market, i|
  market.each do |k, v|
    instance_variable_set "market#{i}_#{k}", v

    # this will define @market0_id = 448  
  end
end