By using actual class constants for classes, instead of strings, doesn't the create a mutual dependency problem?

mutual_dependency.rb

require 'virtus'

class Post
  include Virtus

  attribute :title,    String
  attribute :comments, Array[Comment]
end

class Comment
  include Virtus

  attribute :post, Post
  attribute :body, String
end

# I might want to be able to do this
puts Comment.new(:body => "First Comment", :post => {:title => "First Post"})

# or this
puts Post.new(:title => "First Post", :comments => [{:body => "First Comment"}, {:body => "Second Comment"}]).inspect

# but you can't because depending on which model you define first, Post or Comment, the other one isn't defined yet

# doesn't it need to work like this?

class Post
  include Virtus

  attribute :title,    String
  attribute :comments, Array['Comment']
end

class Comment
  include Virtus

  attribute :post, 'Post'
  attribute :body, String
end