new

# File activerecord/lib/active_record/associations.rb, line 115
    def initialize(owner_class_name = nil, reflection = nil)
      if owner_class_name && reflection
        super("Cannot have a has_many :through association '#{owner_class_name}##{reflection.name}' which goes through the polymorphic association '#{owner_class_name}##{reflection.through_reflection.name}'.")
      else
        super("Cannot have a has_many :through association.")
      end
    end