Best practice for DRYing up New and Edit forms using partial

Question

This should be an easy one, I'm a noob.

I have new and edit views for a model that use a partial to display a form. For the edit form I want to display a field that I do not want to display in the new form.

Should I be passing a local variable stating its in edit mode to the partial and use a condition in the partial to display the field?

Whats the best practice in this case to let the partial know what action called it?

Answer 1

This will only display the field for the new form

<%# app/views/something/_form.html.erb %>

<% form_for something do |form| %>

  <%# common fields ... %>

  <% if something.new_record? %>
    <%= form.text_field :foo %>
  <% end %>

<% end %>

If you want it on the edit form, just switch if to unless