{"action":"created","issue":{"url":"https://api.github.com/repos/cpprefjp/site/issues/360","repository_url":"https://api.github.com/repos/cpprefjp/site","labels_url":"https://api.github.com/repos/cpprefjp/site/issues/360/labels{/name}","comments_url":"https://api.github.com/repos/cpprefjp/site/issues/360/comments","events_url":"https://api.github.com/repos/cpprefjp/site/issues/360/events","html_url":"https://github.com/cpprefjp/site/issues/360","id":143789111,"number":360,"title":"ユーザー定義リテラルの説明について","user":{"login":"kariya-mitsuru","id":2217224,"avatar_url":"https://avatars.githubusercontent.com/u/2217224?v=3","gravatar_id":"","url":"https://api.github.com/users/kariya-mitsuru","html_url":"https://github.com/kariya-mitsuru","followers_url":"https://api.github.com/users/kariya-mitsuru/followers","following_url":"https://api.github.com/users/kariya-mitsuru/following{/other_user}","gists_url":"https://api.github.com/users/kariya-mitsuru/gists{/gist_id}","starred_url":"https://api.github.com/users/kariya-mitsuru/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/kariya-mitsuru/subscriptions","organizations_url":"https://api.github.com/users/kariya-mitsuru/orgs","repos_url":"https://api.github.com/users/kariya-mitsuru/repos","events_url":"https://api.github.com/users/kariya-mitsuru/events{/privacy}","received_events_url":"https://api.github.com/users/kariya-mitsuru/received_events","type":"User","site_admin":false},"labels":[{"url":"https://api.github.com/repos/cpprefjp/site/labels/question","name":"question","color":"cc317c"}],"state":"open","locked":false,"assignee":null,"milestone":null,"comments":12,"created_at":"2016-03-27T08:56:19Z","updated_at":"2016-03-28T01:09:44Z","closed_at":null,"body":"[ユーザー定義リテラル](http://cpprefjp.github.io/lang/cpp11/user_defined_literals.html) の説明で、以下の 2 点について規格での言及箇所が見つからなかったのですが、どちらで言及されてますでしょうか。\r\n\r\n> ユーザー定義リテラルのサフィックスと組み込みリテラルのサフィックスが一致した場合でも、組み込みリテラルのサフィックスと型が一致しない場合には、ユーザー定義リテラルが使用される。たとえば、浮動小数点数のユーザー定義リテラルとしてLLを定義した場合でも、整数リテラルに対してLLサフィックスを付けた場合には、組み込みのLLサフィックスが使用される。\r\n\r\n> 非グローバル名前空間にリテラル演算子を定義すること\r\n\r\nちなみに、前者は Clang ではできませんでした。\r\nhttp://melpon.org/wandbox/permlink/bpXMoqJUZdCuQ65i"},"comment":{"url":"https://api.github.com/repos/cpprefjp/site/issues/comments/202180407","html_url":"https://github.com/cpprefjp/site/issues/360#issuecomment-202180407","issue_url":"https://api.github.com/repos/cpprefjp/site/issues/360","id":202180407,"user":{"login":"k-satoda","id":1337204,"avatar_url":"https://avatars.githubusercontent.com/u/1337204?v=3","gravatar_id":"","url":"https://api.github.com/users/k-satoda","html_url":"https://github.com/k-satoda","followers_url":"https://api.github.com/users/k-satoda/followers","following_url":"https://api.github.com/users/k-satoda/following{/other_user}","gists_url":"https://api.github.com/users/k-satoda/gists{/gist_id}","starred_url":"https://api.github.com/users/k-satoda/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/k-satoda/subscriptions","organizations_url":"https://api.github.com/users/k-satoda/orgs","repos_url":"https://api.github.com/users/k-satoda/repos","events_url":"https://api.github.com/users/k-satoda/events{/privacy}","received_events_url":"https://api.github.com/users/k-satoda/received_events","type":"User","site_admin":false},"created_at":"2016-03-28T01:09:44Z","updated_at":"2016-03-28T01:09:44Z","body":"> しかし、operator\"\"_xがOKでoperator\"\" _xが規約違反というのは、前者は\r\n> 構文的なハックなので、少なくても推奨しないことは記載したいですね。\r\n\r\n（アンダースコア＋小文字始まりのサフィックスであればどちらも問題ない\r\n  ですよね、念のため。 \"... for any use\" のほうの予約を回避できる件だと\r\n  して。）\r\nこれら OK, NG の区別は規格中の例でも明示されているものであり、将来的に\r\n無くなるようなものであればツッコミが入っている可能性が高く、 cpprefjp が\r\n独自に推奨しないとする理由は無いのでは？\r\n\r\n予約識別子の使用に該当してしまう operator\"\" _X は未定義動作になります\r\nので、これについては推奨する・しないという話ではなく、明確にダメとわかる\r\nように書いておくのがいいと思います。"}}