このサイトの中身 PostController class PostController < ApplicationController def post if params[:id] == nil or params[:id] == "" @post = Post.order("created_at desc").limit(1).first else @post = Post.find params[:id] end @next = Post.order("created_at desc").where("created_at < ?", @post.created_at).limit(1).first end def edit @post = Post.find params[:id] rescue @post = Post.new end def feed @posts = Pos