{"action":"opened","issue":{"url":"https://api.github.com/repos/hynek/attrs/issues/13","labels_url":"https://api.github.com/repos/hynek/attrs/issues/13/labels{/name}","comments_url":"https://api.github.com/repos/hynek/attrs/issues/13/comments","events_url":"https://api.github.com/repos/hynek/attrs/issues/13/events","html_url":"https://github.com/hynek/attrs/issues/13","id":89142472,"number":13,"title":"Composition of validators","user":{"login":"cyli","id":223200,"avatar_url":"https://avatars.githubusercontent.com/u/223200?v=3","gravatar_id":"","url":"https://api.github.com/users/cyli","html_url":"https://github.com/cyli","followers_url":"https://api.github.com/users/cyli/followers","following_url":"https://api.github.com/users/cyli/following{/other_user}","gists_url":"https://api.github.com/users/cyli/gists{/gist_id}","starred_url":"https://api.github.com/users/cyli/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/cyli/subscriptions","organizations_url":"https://api.github.com/users/cyli/orgs","repos_url":"https://api.github.com/users/cyli/repos","events_url":"https://api.github.com/users/cyli/events{/privacy}","received_events_url":"https://api.github.com/users/cyli/received_events","type":"User","site_admin":false},"labels":[],"state":"open","locked":false,"assignee":null,"milestone":null,"comments":0,"created_at":"2015-06-17T22:27:17Z","updated_at":"2015-06-17T22:27:17Z","closed_at":null,"body":"I was going to write some composition validators, like `all` (all the given validators have to match), but the more I thought about it the more I basically want all the compositional elements in http://testtools.readthedocs.org/en/latest/for-test-authors.html#matchers.\r\n\r\nI was wondering how you felt about adding a validator that took matchers - it makes it really easy for folks to make custom validation, and [`testtool.matchers`](http://testtools.readthedocs.org/en/latest/for-test-authors.html#matchers) has pretty nice error reporting."}}