A simple Ruby module that, when extended inside a class, will provide a method that will enable the creation of methods that could be used to create nice block-notation setters.

attr_accessor_block.rb

##
# AttrAccessorBlock
#
# This module is to be "extended" (not included) into a class
# Then just invoke the "attr_accessor_block" method, like you would with "attr_accessor"
# This will enable you to make use of "block notations" and "instance_eval" to create "prettier"
# and more "readable" attribute setters.
#
#  class Example
#    extend AttrAccessorBlock
#    attr_accessor_block :example1, :example2, :example3, :etc
#  end
#
module AttrAccessorBlock
  def attr_accessor_block(*attributes)
    attributes.each do |method|
      define_method method do |*value|
        if value = value.first
          instance_variable_set("@#{method}", value)
        else
          instance_variable_get("@#{method}")
        end
      end
      define_method "#{method}=" do |value|
        instance_variable_set("@#{method}", value)
      end
    end    
  end
end

##
# Example Person Class
# Extend the class with AttrAccessorBlock (ClassMethods)
# Use the attr_accessor_block instead of the built-in attr_accessor
#
# attr_accessor_block creates 2 methods, like attr_accessor
# except that the "attribute()" method that's produced will act a bit different
# from the one you get with attr_accessor, the main difference being:
# - If no value is set, e.g. "person.name()", then the @name is returned
# - If a value is set, e.g. "person.name('Michael')", then the @name is set to 'Michael'
# This is to allow for prettier block configurations. Other than that, it practically works the same
# as attr_accessor, you can still also use person.name = 'Michael'
class Person
  
  ##
  # Extend the "AttrAccessorBlock" module
  extend AttrAccessorBlock
  
  ##
  # Define some methods to dynamically generate like you would with "attr_accessor"
  attr_accessor_block :name, :age, :gender
  
  ##
  # For Example 1
  def update_example_1
    yield self
  end
  
  ##
  # For Example 2 and 3
  def update_example_2_and_3(&block)
    instance_eval &block
  end
  
end

##
# Example 1 with "object.attribute = value"
person = Person.new
person.update_example_1 do |object|
  object.name    = 'Michael'
  object.age     = 21
  object.gender  = 'Male'
end
puts person.name, person.age, person.gender

##
# Example 2 with "object.attribute value"
person = Person.new
person.update_example_2_and_3 do |object|
  object.name    'Michael'
  object.age     21
  object.gender  'Male'
end
puts person.name, person.age, person.gender

##
# Example 3 with "attribute value"
person = Person.new
person.update_example_2_and_3 do
  name    'Michael'
  age     21
  gender  'Male'
end
puts person.name, person.age, person.gender