From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me X-Spam-Level: X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00 autolearn=ham autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 103376,e429176c9adb07b X-Google-Attributes: gid103376,public X-Google-ArrivalTime: 2003-02-20 17:25:18 PST Path: archiver1.google.com!news1.google.com!newsfeed.stanford.edu!logbridge.uoregon.edu!arclight.uoregon.edu!wn13feed!worldnet.att.net!204.127.198.203!attbi_feed3!attbi.com!rwcrnsc51.ops.asp.att.net.POSTED!not-for-mail From: tmoran@acm.org Newsgroups: comp.lang.ada Subject: Re: [OT] Best way to isolate a GUI? (The final concensous?) References: <3E55501D.9050006@cogeco.ca> X-Newsreader: Tom's custom newsreader Message-ID: <1ef5a.191182$HN5.823636@rwcrnsc51.ops.asp.att.net> NNTP-Posting-Host: 12.234.13.56 X-Complaints-To: abuse@attbi.com X-Trace: rwcrnsc51.ops.asp.att.net 1045790717 12.234.13.56 (Fri, 21 Feb 2003 01:25:17 GMT) NNTP-Posting-Date: Fri, 21 Feb 2003 01:25:17 GMT Organization: AT&T Broadband Date: Fri, 21 Feb 2003 01:25:17 GMT Xref: archiver1.google.com comp.lang.ada:34322 Date: 2003-02-21T01:25:17+00:00 List-Id: > I don't think you can easily avoid callbacks. I think of callbacks (whether done with function pointers or overriding a tagged type's primitive ops) as interrupts. Does anyone use the Real-Time Systems Annex Interrupt handling stuff for callbacks? If you think of callbacks as equivalent to a series of guarded "accept"s in a giant "select" in a loop, where the guard handles callback registration, then that's clearly a highly restricted special case of tasking. Both that and the interrupt model assume that a callback has complete control for a short time until its event is, in some sense, completed. Awfully restrictive style, but perhaps appropriate for the millions of programmers unfamiliar with the ins and outs of multi-tasking programming.