Mastering Ruby Closures

Block Pattern #3: Beautiful Object Initialization

There are a couple of ways to initialize an object in Ruby. Oftentimes, this is under the guise of applying configuration on an object. They usually mean the same thing. Here’s an example taken from the Twitter Ruby Gem:^[4]

client = Twitter::REST::Client.new do |config|
  config.consumer_key        = "YOUR_CONSUMER_KEY"
  config.consumer_secret     = "YOUR_CONSUMER_SECRET"
  config.access_token        = "YOUR_ACCESS_TOKEN"
  config.access_token_secret = "YOUR_ACCESS_SECRET"
end

See if you can guess at how this is implemented. Here’s a hint: consumer_key and the rest belong to accessors of Twitter::REST::Client. You’re going to build the bare minimum to get the preceding code to work. The code is ...