{"action":"created","issue":{"url":"https://api.github.com/repos/JukkaL/mypy/issues/406","labels_url":"https://api.github.com/repos/JukkaL/mypy/issues/406/labels{/name}","comments_url":"https://api.github.com/repos/JukkaL/mypy/issues/406/comments","events_url":"https://api.github.com/repos/JukkaL/mypy/issues/406/events","html_url":"https://github.com/JukkaL/mypy/issues/406","id":40950276,"number":406,"title":"Wrong type in list after isinstance check","user":{"login":"AlexElvers","id":515230,"avatar_url":"https://avatars.githubusercontent.com/u/515230?v=3","gravatar_id":"","url":"https://api.github.com/users/AlexElvers","html_url":"https://github.com/AlexElvers","followers_url":"https://api.github.com/users/AlexElvers/followers","following_url":"https://api.github.com/users/AlexElvers/following{/other_user}","gists_url":"https://api.github.com/users/AlexElvers/gists{/gist_id}","starred_url":"https://api.github.com/users/AlexElvers/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/AlexElvers/subscriptions","organizations_url":"https://api.github.com/users/AlexElvers/orgs","repos_url":"https://api.github.com/users/AlexElvers/repos","events_url":"https://api.github.com/users/AlexElvers/events{/privacy}","received_events_url":"https://api.github.com/users/AlexElvers/received_events","type":"User","site_admin":false},"labels":[{"url":"https://api.github.com/repos/JukkaL/mypy/labels/enhancement%20proposal","name":"enhancement proposal","color":"bfdadc"}],"state":"closed","locked":false,"assignee":null,"milestone":null,"comments":3,"created_at":"2014-08-22T21:05:19Z","updated_at":"2015-05-17T17:49:00Z","closed_at":"2015-05-17T17:49:00Z","body":"The following code appends a str to a list of ints.\r\n\r\n```Python\r\nfrom typing import Iterable, List\r\n\r\ndef modify(l: Iterable[object]) -> None:\r\n    if isinstance(l, List[object]):\r\n        l.append(\"abc\")\r\n\r\nl = List[int]()\r\nmodify(l)\r\nprint(l)  # ['abc']\r\n1 + l[0]  # TypeError: unsupported operand type(s) for +: 'int' and 'str'\r\n```\r\n\r\n(without mypy errors/warnings)"},"comment":{"url":"https://api.github.com/repos/JukkaL/mypy/issues/comments/102826870","html_url":"https://github.com/JukkaL/mypy/issues/406#issuecomment-102826870","issue_url":"https://api.github.com/repos/JukkaL/mypy/issues/406","id":102826870,"user":{"login":"JukkaL","id":1107911,"avatar_url":"https://avatars.githubusercontent.com/u/1107911?v=3","gravatar_id":"","url":"https://api.github.com/users/JukkaL","html_url":"https://github.com/JukkaL","followers_url":"https://api.github.com/users/JukkaL/followers","following_url":"https://api.github.com/users/JukkaL/following{/other_user}","gists_url":"https://api.github.com/users/JukkaL/gists{/gist_id}","starred_url":"https://api.github.com/users/JukkaL/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/JukkaL/subscriptions","organizations_url":"https://api.github.com/users/JukkaL/orgs","repos_url":"https://api.github.com/users/JukkaL/repos","events_url":"https://api.github.com/users/JukkaL/events{/privacy}","received_events_url":"https://api.github.com/users/JukkaL/received_events","type":"User","site_admin":false},"created_at":"2015-05-17T17:49:00Z","updated_at":"2015-05-17T17:49:00Z","body":"Closing this as this doesn't seem like a high-priority issue."}}