class Module
  # Take the name of a variable containing a hash and a list of keys
  # and define getter methods for those hash items
  # Keys need to be symbols or strings
  def hash_reader(hashvar, *keys)
    keys.each do |key|
      define_method(key) do
        hash = instance_variable_get hashvar
        hash[key]
      end
    end
  end
end

class Foo
  hash_reader :@foo, :foo, :bar, :baz

  def initialize(foo)
    @foo=foo
  end
end

Foo.new(:foo => "bar", :bar => 42, :baz => 23).bar
#=> 42