open_struct_deep.rb

require 'ostruct'

class OpenStruct
  DEPTH = 5
  def self.deep(data, depth=0, &blck)
    return data if depth > DEPTH
    return data unless data.class == Hash
    hash = {}
    data.each do |key, value|
      key = blck.call(key) if block_given?
      case value
      when Hash
        hash[key] = OpenStruct.deep(value, depth + 1, &blck)
      when Array
        hash[key] = value.map{ |element| OpenStruct.deep(element, depth + 1, &blck) }
      else
        hash[key] = value
      end
    end
    OpenStruct.new(hash)
  end
end

if __FILE__ == $PROGRAM_NAME
  require 'pp'

  data = {
    :data => 0,
    :depth1 => {
      :data => 1,
      :depth2 => {
        :data => 2,
        :depth3 => {
          :data => 3,
          :depth4 => {
            :data => 4,
            :depth5 => {
              :data => 5,
              :depth6 => {
                :data => 6,
              },
            },
          },
        },
      },
    },
  }
  value = OpenStruct.deep(data)
  value.data
  # => 0
  value.depth1.data
  # => 1
  value.depth1.depth2.data
  # => 2
  value.depth1.depth2.depth3.data
  # => 3
  value.depth1.depth2.depth3.depth4.data
  # => 4
  value.depth1.depth2.depth3.depth4.depth5.data
  # => 5
  value.depth1.depth2.depth3.depth4.depth5.depth6[:data]
  # => 6

  value = OpenStruct.deep(data) do |key|
    key.to_s.upcase
  end
  value.DATA
  # => 0
  value.DEPTH1.DATA
  # => 1
  value.DEPTH1.DEPTH2.DATA
  # => 2
  value.DEPTH1.DEPTH2.DEPTH3.DATA
  # => 3
  value.DEPTH1.DEPTH2.DEPTH3.DEPTH4.DATA
  # => 4
  value.DEPTH1.DEPTH2.DEPTH3.DEPTH4.DEPTH5.DATA
  # => 5
  value.DEPTH1.DEPTH2.DEPTH3.DEPTH4.DEPTH5.DEPTH6[:data]
  # => 6

  data = {
    :ary => [ 1,
              {
                :data => 1,
                :ary  => [1,2,3,],
              },
              3, ],
    :data => 0
  }
  value = OpenStruct.deep(data)
  value.data
  # => 0
  value.ary[0]
  # => 1
  value.ary[2]
  # => 3
  value.ary[1]
  # => #<OpenStruct ...>
  value.ary[1].data
  # => 1
  value.ary[1].ary
  # => [1, 2, 3]
end