case x - Advanced techniques

• when String - matching object class
• when (1..10) - matching ranges
• when /BAR$/ - matching regular expressions
• when -> (n) { n.to_s == "40" } - Matching procs and lambdas
• when Success - Writing your own matcher classes

simple as defining your own === method

class Success
  def self.===(item)
    item.status >= 200 && item.status < 300
  end
end