{"comment":{"url":"https://api.github.com/repos/liyaodong/nodeschool/comments/12147878","html_url":"https://github.com/liyaodong/nodeschool/commit/474a34cbe46b3d2ed37603e768b331ab5ff87cf0#commitcomment-12147878","id":12147878,"user":{"login":"liyaodong","id":3196361,"avatar_url":"https://avatars.githubusercontent.com/u/3196361?v=3","gravatar_id":"","url":"https://api.github.com/users/liyaodong","html_url":"https://github.com/liyaodong","followers_url":"https://api.github.com/users/liyaodong/followers","following_url":"https://api.github.com/users/liyaodong/following{/other_user}","gists_url":"https://api.github.com/users/liyaodong/gists{/gist_id}","starred_url":"https://api.github.com/users/liyaodong/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/liyaodong/subscriptions","organizations_url":"https://api.github.com/users/liyaodong/orgs","repos_url":"https://api.github.com/users/liyaodong/repos","events_url":"https://api.github.com/users/liyaodong/events{/privacy}","received_events_url":"https://api.github.com/users/liyaodong/received_events","type":"User","site_admin":false},"position":null,"line":null,"path":"","commit_id":"474a34cbe46b3d2ed37603e768b331ab5ff87cf0","created_at":"2015-07-14T04:56:51Z","updated_at":"2015-07-14T04:56:51Z","body":"official solution:\r\n```javascript\r\nfunction duckCount() {\r\n  return Array.prototype.slice.call(arguments).filter(function(obj) {\r\n    return Object.prototype.hasOwnProperty.call(obj, 'quack')\r\n  }).length\r\n}\r\n\r\nmodule.exports = duckCount\r\n```\r\n"}}