{"action":"created","issue":{"url":"https://api.github.com/repos/rust-lang/rust/issues/20813","labels_url":"https://api.github.com/repos/rust-lang/rust/issues/20813/labels{/name}","comments_url":"https://api.github.com/repos/rust-lang/rust/issues/20813/comments","events_url":"https://api.github.com/repos/rust-lang/rust/issues/20813/events","html_url":"https://github.com/rust-lang/rust/issues/20813","id":53896494,"number":20813,"title":"`Cell` should be `Copy`","user":{"login":"pythonesque","id":923144,"avatar_url":"https://avatars.githubusercontent.com/u/923144?v=3","gravatar_id":"","url":"https://api.github.com/users/pythonesque","html_url":"https://github.com/pythonesque","followers_url":"https://api.github.com/users/pythonesque/followers","following_url":"https://api.github.com/users/pythonesque/following{/other_user}","gists_url":"https://api.github.com/users/pythonesque/gists{/gist_id}","starred_url":"https://api.github.com/users/pythonesque/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/pythonesque/subscriptions","organizations_url":"https://api.github.com/users/pythonesque/orgs","repos_url":"https://api.github.com/users/pythonesque/repos","events_url":"https://api.github.com/users/pythonesque/events{/privacy}","received_events_url":"https://api.github.com/users/pythonesque/received_events","type":"User","site_admin":false},"labels":[{"url":"https://api.github.com/repos/rust-lang/rust/labels/A-libs","name":"A-libs","color":"d7e102"}],"state":"closed","locked":false,"assignee":null,"milestone":null,"comments":9,"created_at":"2015-01-09T18:05:14Z","updated_at":"2015-01-11T15:22:08Z","closed_at":"2015-01-10T17:41:43Z","body":"I'm not really sure why it isn't.  It can only ever hold `Copy` data and `Cell::new(some_cell.get())` has the same effect as a memcpy, so the effect of not making it `Copy` is mostly to just make it annoying to use types with `Cell`s in them (since you can't `#[derive(Copy)]` on them, use them with the  `[Foo ; n]` instantiation syntax in fixed-size arrays, put them in other `Cell`s, etc.)."},"comment":{"url":"https://api.github.com/repos/rust-lang/rust/issues/comments/69497934","html_url":"https://github.com/rust-lang/rust/issues/20813#issuecomment-69497934","issue_url":"https://api.github.com/repos/rust-lang/rust/issues/20813","id":69497934,"user":{"login":"Gankro","id":1136864,"avatar_url":"https://avatars.githubusercontent.com/u/1136864?v=3","gravatar_id":"","url":"https://api.github.com/users/Gankro","html_url":"https://github.com/Gankro","followers_url":"https://api.github.com/users/Gankro/followers","following_url":"https://api.github.com/users/Gankro/following{/other_user}","gists_url":"https://api.github.com/users/Gankro/gists{/gist_id}","starred_url":"https://api.github.com/users/Gankro/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/Gankro/subscriptions","organizations_url":"https://api.github.com/users/Gankro/orgs","repos_url":"https://api.github.com/users/Gankro/repos","events_url":"https://api.github.com/users/Gankro/events{/privacy}","received_events_url":"https://api.github.com/users/Gankro/received_events","type":"User","site_admin":false},"created_at":"2015-01-11T15:22:08Z","updated_at":"2015-01-11T15:22:08Z","body":"Whoops, sorry I keep ADD'ing away every time I start writing a comment here. You know, like, re-installing my entire OS. :camel:  \r\n\r\nBasically what @huonw said. In my mind Cell is basically a container or smaht-pointer type. It's not really \"plain old data\" (it contains an UnsafeCell!). But mostly I think we just want to be conservative here."}}