Article 14004 of comp.sys.newton.programmer: Path: hustle.rahul.net!rahul.net!a2i!bug.rahul.net!rahul.net!a2i!samba.rahul.net!rahul.net!a2i!news.PBI.net!news.mathworks.com!nntp.primenet.com!news1.best.com!nntp1.best.com!usenet From: "Walter Smith" Newsgroups: comp.sys.newton.programmer Subject: Re: error 77 Date: Tue, 16 Jul 1996 15:08:58 -0700 Organization: Best Internet Communications Lines: 35 Message-ID: <01bb7364.6e34d2a0$520456ce@wsmith.microsoft.com> References: <31EBDC8B.41C6@sluvca.slu.edu> NNTP-Posting-Host: wsmith.vip.best.com X-Newsreader: Microsoft Internet News 4.70.1080 > evt.ex.abt.bus > 77 Newton programming folklore alert: That means you left a pointer into your package in the system when your package was removed. Often, when that happens, you get a comprehensible error to that effect, but there's one place in the system (namely, searching a frame for a slot name) where we couldn't afford the test, so you get an unfriendly error. > routing.(kAppSymbol):=partFrame.theForm.myRoutingFrame; You're leaving a reference to a symbol (kAppSymbol) from your package in the "routing" frame. When your package is removed, references to objects in your package are changed to the value (whose decimal representation is, not coincidentally, 77). Anybody who looks at the routing frame thereafter and happens to run across the slot with as the tag will get a bus error. > and the remove script is: > RemoveSlot(routing, 'kAppSymbol); This code is a good example of something that will search the routing frame and run into the ! (Also, aside from that, I don't think you meant to quote kAppSymbol.) The answer is simple--don't put a reference to your package in the routing frame. Internalize the symbol instead, so the routing frame has a reference to a symbol that won't go away when your package does: routing.(EnsureInternal(kAppSymbol)):=partFrame.theForm.myRoutingFrame; - W -- Walter Smith wrs@pobox.com http://www.pobox.com/~wrs/