# postのインスタンスを作成 irb > post = Post.new => #<Post id: nil, title: nil, created_at: nil, updated_at: nil> # 空のインスタンスを確認 irb > post => #<Post id: nil, title: nil, created_at: nil, updated_at: nil> # post.author_postsの確認 # 空のArray irb > post.author_posts => #<ActiveRecord::Associations::CollectionProxy []> # post.authorsの確認 # 空のArray irb > post.authors => #<ActiveRecord::Associations::CollectionProxy
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