{"action":"created","issue":{"url":"https://api.github.com/repos/rust-lang/rust/issues/27517","repository_url":"https://api.github.com/repos/rust-lang/rust","labels_url":"https://api.github.com/repos/rust-lang/rust/issues/27517/labels{/name}","comments_url":"https://api.github.com/repos/rust-lang/rust/issues/27517/comments","events_url":"https://api.github.com/repos/rust-lang/rust/issues/27517/events","html_url":"https://github.com/rust-lang/rust/issues/27517","id":99003555,"number":27517,"title":"Add `ByNeed` and `Predicate` traits","user":{"login":"SimonSapin","id":291359,"avatar_url":"https://avatars.githubusercontent.com/u/291359?v=3","gravatar_id":"","url":"https://api.github.com/users/SimonSapin","html_url":"https://github.com/SimonSapin","followers_url":"https://api.github.com/users/SimonSapin/followers","following_url":"https://api.github.com/users/SimonSapin/following{/other_user}","gists_url":"https://api.github.com/users/SimonSapin/gists{/gist_id}","starred_url":"https://api.github.com/users/SimonSapin/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/SimonSapin/subscriptions","organizations_url":"https://api.github.com/users/SimonSapin/orgs","repos_url":"https://api.github.com/users/SimonSapin/repos","events_url":"https://api.github.com/users/SimonSapin/events{/privacy}","received_events_url":"https://api.github.com/users/SimonSapin/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"},{"url":"https://api.github.com/repos/rust-lang/rust/labels/B-RFC-approved","name":"B-RFC-approved","color":"e102d8"},{"url":"https://api.github.com/repos/rust-lang/rust/labels/T-libs","name":"T-libs","color":"bfd4f2"}],"state":"closed","locked":false,"assignee":null,"milestone":null,"comments":5,"created_at":"2015-08-04T16:05:10Z","updated_at":"2016-02-18T18:49:19Z","closed_at":"2016-02-18T18:49:19Z","body":"#18424 \"Implement collections reform\" was closed with one part left not implemented yet:\r\n\r\n> Tracking issue for rust-lang/rfcs#235, there are a number of sub-issues associated with this:\r\n>\r\n> [...]\r\n>\r\n> Backwards compatible changes that will require additional language features:\r\n>\r\n> * [ ] [Add `ByNeed` and `Predicate` traits](https://github.com/rust-lang/rfcs/blob/master/text/0235-collections-conventions.md#minimizing-variants-byneed-and-predicate-traits) (needs negative bounds to work with unboxed closures)\r\n\r\nIn particular, making `Iterator::position` generic over a `Predicate` trait would help replacing `[T]::position_elem`, which was deprecated in https://github.com/rust-lang/rust/pull/26914, without the verbosity of `.position(|i| i == &x)`\r\n\r\nCC @alexcrichton, @aturon "},"comment":{"url":"https://api.github.com/repos/rust-lang/rust/issues/comments/185855975","html_url":"https://github.com/rust-lang/rust/issues/27517#issuecomment-185855975","issue_url":"https://api.github.com/repos/rust-lang/rust/issues/27517","id":185855975,"user":{"login":"alexcrichton","id":64996,"avatar_url":"https://avatars.githubusercontent.com/u/64996?v=3","gravatar_id":"","url":"https://api.github.com/users/alexcrichton","html_url":"https://github.com/alexcrichton","followers_url":"https://api.github.com/users/alexcrichton/followers","following_url":"https://api.github.com/users/alexcrichton/following{/other_user}","gists_url":"https://api.github.com/users/alexcrichton/gists{/gist_id}","starred_url":"https://api.github.com/users/alexcrichton/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/alexcrichton/subscriptions","organizations_url":"https://api.github.com/users/alexcrichton/orgs","repos_url":"https://api.github.com/users/alexcrichton/repos","events_url":"https://api.github.com/users/alexcrichton/events{/privacy}","received_events_url":"https://api.github.com/users/alexcrichton/received_events","type":"User","site_admin":false},"created_at":"2016-02-18T18:49:19Z","updated_at":"2016-02-18T18:49:19Z","body":"Lots of time has passed since these were originally designed, so they would likely basically require another RFC to be added today, so closing."}}