# Law Of Demeter: Every unit should have limited knowledge about other units, simply don't talk to strangers!
# 2 dots are fair enough!

# BAD
class Invoice < ActiveRecord::Base
 belongs_to :user
end

# In model/view
invoice.user.name

# Good
class Invoice < ActiveRecord::Base
 belongs_to :user
 delegate :name, to: :user, prefix: true
end

invoice.user_name