Mini Ruby DSL Template

Spawning quick DSLs for fun and profit is super easy with Ruby. This toy is a template for stealing for something useful.

Let’s imagine a hypothetical, and not very useful, mini-DSL of the form:

Blog.post do
  title { 'Hello World' }
  body { 'Hello from the Bellerophon' }
end

How would we model that in code?

class Blog

  def self.post(&block)
    blog_post = Blog.new
    blog_post.instance_eval(&block) if block_given?
    blog_post
  end

  def title(&block)
    @title = block.call(self) if block_given?
    @title
  end

  def body(&block)
    @body = block.call(self) if block_given?
    @body
  end

  private
  def initialize 
    @title = nil
    @body = nil
  end
end