# File app/controllers/conferences_controller.rb, line 69
  def sign_up
    registrations_sanity_checks or return false

    # Avoid silly mistakes due to reloads
    return if @user.conferences.include? @conference
    if @user.register_for(@conference)
      flash[:notice] << _('You have successfully registered for ' +
                          'conference "%s"') % @conference.name
    else
      flash[:error] << _('Could not register you for conference %s: %s') %
        [@conference.name, @user.errors.full_messages]
    end
  end