form_for(@address) in form controller says undefined local variable 'address_params'

Something in my routes? I’m using nested resources

resources :users do

resources :addresses


Being that you've got nested resources the form is looking for the @user info too, define the user in your address controller actions too and then pass it into your form like so: ([@user, @address]). That should get you on the right path. Try a Google of 'rails form_for nested resources' and see what you discover, happy exploring!