gistfile1.txt

foo = { "bar" => "baz" }

def quuxify(bar)
  bar["bar"] = "quux"
end

foo               #=> {"bar"=>"baz"}

quuxify(foo)

foo               #=> {"bar"=>"quux"}

gistfile2.rb

def linearize(data)
  nodes = {}

  traverse = lambda do |node|
    if node.is_a?(Hash)
      node.each do |key, val|
        if val.is_a?(Hash)
          node[key] = {
            "ref" => traverse.call(val)
          }
        end
        if val.is_a?(Array)
          traverse.call(val)
        end
      end
    elsif node.is_a?(Array)
      node.each_with_index do |item, idx|
        node[idx] = {
          "ref" => traverse.call(item)
        }
      end
    end
    nodes[nodes.length] = node
    return nodes.length - 1
  end

  traverse.call(data)
  nodes
end