{"action":"opened","issue":{"url":"https://api.github.com/repos/racket/macro-debugger/issues/13","repository_url":"https://api.github.com/repos/racket/macro-debugger","labels_url":"https://api.github.com/repos/racket/macro-debugger/issues/13/labels{/name}","comments_url":"https://api.github.com/repos/racket/macro-debugger/issues/13/comments","events_url":"https://api.github.com/repos/racket/macro-debugger/issues/13/events","html_url":"https://github.com/racket/macro-debugger/issues/13","id":131461407,"number":13,"title":"Macro stepper error (steps)","user":{"login":"howell","id":3951940,"avatar_url":"https://avatars.githubusercontent.com/u/3951940?v=3","gravatar_id":"","url":"https://api.github.com/users/howell","html_url":"https://github.com/howell","followers_url":"https://api.github.com/users/howell/followers","following_url":"https://api.github.com/users/howell/following{/other_user}","gists_url":"https://api.github.com/users/howell/gists{/gist_id}","starred_url":"https://api.github.com/users/howell/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/howell/subscriptions","organizations_url":"https://api.github.com/users/howell/orgs","repos_url":"https://api.github.com/users/howell/repos","events_url":"https://api.github.com/users/howell/events{/privacy}","received_events_url":"https://api.github.com/users/howell/received_events","type":"User","site_admin":false},"labels":[],"state":"open","locked":false,"assignee":null,"milestone":null,"comments":0,"created_at":"2016-02-04T20:14:24Z","updated_at":"2016-02-04T20:14:24Z","closed_at":null,"body":"The macro stepper reports an error and is essentially an unusable on a fairly straightforward file.\r\n\r\nThe error is:\r\n\r\n> Macro stepper error (steps).  Original syntax:\r\n\r\nfollowed by the contents of my file.\r\n\r\nThere appears to be some non-determinism- there was one try where the macro stepper worked fine on the same file. The vast majority of the time it errors.\r\n\r\nOn a couple of occasions I have gotten error messages from DrRacket of the form:\r\n\r\n> sequence-contract-violation: negative: method set-max-width cannot be called, except in states (unlocked write-lock), args 823\r\n\r\nA file that exhibits this behavior for me is copied here:  https://gist.github.com/howell/bf4da4be3ca72b940162"}}