Undefined method `merge' for '####':string <%= form_for %> helper

Question

I have a form, that when POSTed, renders another form. What I would like to do is to pass the parameters from the first form, into certain hidden fields of the second form.

Answer 1

second parameter in hidden_field should be an option hash, not a value

<%= f.hidden_field :original_number, :value => params[:original_number] %>