How can one set property values when initializing an object in Ruby?

Question

Given the following class:

class Test
  attr_accessor :name
end

When I create the object, I want to do the following:

t = Test         


        

Answer 1

There is a general way of doing complex object initialization by passing a block with necessary actions. This block is evaluated in the context of the object to be initialized, so you have an easy access to all instance variables and methods.

Continuing your example, we can define this generic initializer:

class Test
  attr_accessor :name

  def initialize(&block)
    instance_eval(&block)
  end 
end

and then pass it the appropriate code block:

t = Test.new { @name = 'name' }

or

t = Test.new do
  self.name = 'name'
  # Any other initialization code, if needed.
end

Note that this approach does not require adding much complexity to the initialize method, per se.