Is it possible to use delegate in your Active Record model and use conditions like
class User < ApplicationRecord
delegate :company, :to => :master, :if => :has_master?
belongs_to :master, :class_name => "User"
No, you can't, but you can pass the
:allow_nil => true option to return nil if the master is nil.
class User < ActiveRecord::Base delegate :company, :to => :master, :allow_nil => true # ... end user.master = nil user.company # => nil user.master = <#User ...> user.company # => ...
Otherwise, you need to write your own custom method instead using the delegate macro for more complex options.
class User < ActiveRecord::Base # ... def company master.company if has_master? end end