class Article < Struct.new(:id, :title); end class CommentsController < ApplicationController breadcrumb lambda { |c| c.find_article(c.params[:post_id]).title }, lambda { |c| c.post_comments_path(c.params[:post_id]) } breadcrumb -> { find_article(params[:post_id]).title + " No Controller" }, -> { post_comments_path(params[:post_id], no_controller: true) } def index end def show end def find_article(id) ::Article.new(id, 'Post comments') end end