form_for non-AR model - fields_for Array attribute doesn't iterate

Question

I\'m having trouble getting fields_for to work on an Array attribute of a non-ActiveRecord model.

Distilled down, I have to following:

models/pa

Answer 1

I think the correct technique is:

= form_for @parent, :url => new_parent_path do |f|
  - @parent.bars.each do |bar|
    = f.fields_for "bars[]", bar do |r|
      = r.object.inspect

Quite why it can't be made to Just Work I'm not sure, but this seems to do the trick.