If I have the following nested model relationships (all has_many): Countries < Cities < Streets < Homes
In a show view, how can I check if a particular Country has any homes?
Edit: Adding the suggested method of chaining with the map method (first try to map to streets). So far it's not restricting the records
<% @countries.each do |country| %>
<% if country.cities.map(&:streets).any? %>
....
<% end %>
<% end %>
You can call or @country.cities.map(&:streets).flatten.map(&:homes).present? or @country.cities.map(&:streets).map(&:homes).any?
<% if @country.cities.map(&:streets).flatten.map(&:homes).flatten.any? %>
Tro-lol-lo yo-lo-puki
<% end %>
Also you can wrap this long line into your model method:
class Country < ActiveRecord::Base
def any_homes?
cities.map(&:streets).flatten.map(&:homes).flatten.any?
end
end
Usage
<% if @country.any_homes? %>
Tro-lol-lo yo-lo-puki
<% end %>
And of course it looks like a good data structure for refactoring! It wants to be refactored!
country.cities.map(&:streets).flatten.any?