ActiveParams (working title)

edit_account_params.rb

# app/params/edit_account_params.rb
class EditAccountParams < ActiveParams::Base
  attributes :first_name,
             :last_name,
             :email,
             :password
  
  validates_presence_of :first_name, :last_name
  
  has_many :addresses do
    attributes :address1,
               :city,
               :state,
               :zip
  end
  
end

signup_params.rb

# app/params/signup_params.rb
class SignupParams < ActiveParams::Base
  attributes  :first_name,
              :last_name,
              :email,
              :password
  
  has_many :addresses do
    attributes :street,
               :city,
               :state,
               :zip
    
    validates_presence_of :street
  end
  
  has_one :job do
    attribute :company
    attribute :title
  end
  
  validates_confirmation_of :password
end

users_controller.rb

class UsersController < ApplicationController
  
  def new
    @signup = SignupParams.new(params)
  end
  
  def create
    @signup = SignupParams.new(params)

    if @signup.save
      redirect_to @signup
    else
      render :new
    end
  end
  
  def edit
    # model_for can also use send(:attribute) on all the passed in objects to initialize a named parameter set
    @edit_form = EditAccountParams.new(User.find(params[:id]))
  end
  
end