{"action":"created","issue":{"url":"https://api.github.com/repos/Microsoft/visualfsharp/issues/935","repository_url":"https://api.github.com/repos/Microsoft/visualfsharp","labels_url":"https://api.github.com/repos/Microsoft/visualfsharp/issues/935/labels{/name}","comments_url":"https://api.github.com/repos/Microsoft/visualfsharp/issues/935/comments","events_url":"https://api.github.com/repos/Microsoft/visualfsharp/issues/935/events","html_url":"https://github.com/Microsoft/visualfsharp/issues/935","id":131908405,"number":935,"title":"FSC allows bogus inheritance where FSI issues error","user":{"login":"latkin","id":5943573,"avatar_url":"https://avatars.githubusercontent.com/u/5943573?v=3","gravatar_id":"","url":"https://api.github.com/users/latkin","html_url":"https://github.com/latkin","followers_url":"https://api.github.com/users/latkin/followers","following_url":"https://api.github.com/users/latkin/following{/other_user}","gists_url":"https://api.github.com/users/latkin/gists{/gist_id}","starred_url":"https://api.github.com/users/latkin/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/latkin/subscriptions","organizations_url":"https://api.github.com/users/latkin/orgs","repos_url":"https://api.github.com/users/latkin/repos","events_url":"https://api.github.com/users/latkin/events{/privacy}","received_events_url":"https://api.github.com/users/latkin/received_events","type":"User","site_admin":false},"labels":[],"state":"open","locked":false,"assignee":null,"milestone":null,"comments":1,"created_at":"2016-02-06T22:59:03Z","updated_at":"2016-02-07T11:03:21Z","closed_at":null,"body":"```fsharp\r\ntype A(i : int) = class end\r\n\r\ntype B = class inherit A end\r\n```\r\n\r\nIn FSI I get an error that's not super clear but at least reminds me I'm doing something suspicious with omitting constructors: `error FS0193: Parent does not have a default constructor. The default constructor must be explicitly defined.`\r\n\r\nFSC compiles this code without errors or warnings, though. There is no way to create an instance of `B`, but the code is verifiable.\r\n\r\nSince `B` is fairly nonsensical it seems right to have an error."},"comment":{"url":"https://api.github.com/repos/Microsoft/visualfsharp/issues/comments/180996386","html_url":"https://github.com/Microsoft/visualfsharp/issues/935#issuecomment-180996386","issue_url":"https://api.github.com/repos/Microsoft/visualfsharp/issues/935","id":180996386,"user":{"login":"dsyme","id":7204669,"avatar_url":"https://avatars.githubusercontent.com/u/7204669?v=3","gravatar_id":"","url":"https://api.github.com/users/dsyme","html_url":"https://github.com/dsyme","followers_url":"https://api.github.com/users/dsyme/followers","following_url":"https://api.github.com/users/dsyme/following{/other_user}","gists_url":"https://api.github.com/users/dsyme/gists{/gist_id}","starred_url":"https://api.github.com/users/dsyme/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/dsyme/subscriptions","organizations_url":"https://api.github.com/users/dsyme/orgs","repos_url":"https://api.github.com/users/dsyme/repos","events_url":"https://api.github.com/users/dsyme/events{/privacy}","received_events_url":"https://api.github.com/users/dsyme/received_events","type":"User","site_admin":false},"created_at":"2016-02-07T11:03:21Z","updated_at":"2016-02-07T11:03:21Z","body":"This by-design according to the F# language spec.  As you say the code is verifiable - there is no requirement to define a constructor on a class type in F#."}}