tl;dr wtfを使おう 概要(というか全部) pryにはwtfというコマンドがあります。これは最後に起こったエラーのバックトレースを数行表示してくれるものです。これだけでも便利ですが、バックトレースが全部欲しいときはwtf!?のように、!や?を後置するといけます。しかもこれ、いくつでも大丈夫です。なので、 wtf!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
![wtf!!!!!!!!!!!!!!!!!!!!!!?????????????????? - Qiita](https://cdn-ak-scissors.b.st-hatena.com/image/square/edd9439bfe95ae053d5b31f5cce21c59a17239c5/height=288;version=1;width=512/https%3A%2F%2Fqiita-user-contents.imgix.net%2Fhttps%253A%252F%252Fcdn.qiita.com%252Fassets%252Fpublic%252Farticle-ogp-background-9f5428127621718a910c8b63951390ad.png%3Fixlib%3Drb-4.0.0%26w%3D1200%26mark64%3DaHR0cHM6Ly9xaWl0YS11c2VyLWNvbnRlbnRzLmltZ2l4Lm5ldC9-dGV4dD9peGxpYj1yYi00LjAuMCZ3PTkxNiZoPTMzNiZ0eHQ9d3RmJTIxJTIxJTIxJTIxJTIxJTIxJTIxJTIxJTIxJTIxJTIxJTIxJTIxJTIxJTIxJTIxJTIxJTIxJTIxJTIxJTIxJTIxJTNGJTNGJTNGJTNGJTNGJTNGJTNGJTNGJTNGJTNGJTNGJTNGJTNGJTNGJTNGJTNGJTNGJTNGJnR4dC1jb2xvcj0lMjMyMTIxMjEmdHh0LWZvbnQ9SGlyYWdpbm8lMjBTYW5zJTIwVzYmdHh0LXNpemU9NTYmdHh0LWNsaXA9ZWxsaXBzaXMmdHh0LWFsaWduPWxlZnQlMkN0b3Amcz0wZDRmY2E4MTk5YTZiNWU3MWVkYzJmY2M2YTE5M2RlYg%26mark-x%3D142%26mark-y%3D112%26blend64%3DaHR0cHM6Ly9xaWl0YS11c2VyLWNvbnRlbnRzLmltZ2l4Lm5ldC9-dGV4dD9peGxpYj1yYi00LjAuMCZ3PTYxNiZ0eHQ9JTQwb2t1cmFtYXNhZnVtaSZ0eHQtY29sb3I9JTIzMjEyMTIxJnR4dC1mb250PUhpcmFnaW5vJTIwU2FucyUyMFc2JnR4dC1zaXplPTM2JnR4dC1hbGlnbj1sZWZ0JTJDdG9wJnM9YWQyYTg2OWYzZDU2ZDgzNTFlMmJmM2IyMTdmZWYzNDc%26blend-x%3D142%26blend-y%3D491%26blend-mode%3Dnormal%26s%3D7572491ff48437a79cf4c7638924a287)