gistfile1.txt

require 'rubygems'
require 'activesupport'

class Hash
  class Path
    def initialize(hash)
      @hash = hash
    end

    def [](path)
      key, item = last_item(path)
      item[symbolize_key(key)]
    end

    def []=(path, value)
      key, item = last_item(path)
      item[symbolize_key(key)] = value
    end

    private

    def last_item(path)
      path = path.split('/')
      return path.pop, path.inject(@hash) { |hash, key| hash[symbolize_key(key)] }
    end

    def symbolize_key(key)
      key.start_with?(':') ? eval(key) : key
    end
  end

  def path
    Path.new(self)
  end
end

# read

puts({:a => {:b => :c}}.path[':a/:b'].inspect)
puts({'a' => {'b' => 'c'}}.path['a/b'].inspect)
puts({'a' => {:b => :c}}.path['a/:b'].inspect)
puts({'a' => {'b' => :c}}.path['a/b'].inspect)


# write
h = {'a' => {'b' => {}}}
h.path['a'] = 'test'
puts(h.inspect)