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=-1.3 required=5.0 tests=BAYES_00,INVALID_MSGID autolearn=no autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 103376,ca0b11ae1c9a00cb X-Google-Attributes: gid103376,public From: eachus@spectre.mitre.org (Robert I. Eachus) Subject: Re: Papers saying Ada as an overly complex language and hard to implement Date: 1998/03/05 Message-ID: #1/1 X-Deja-AN: 331214133 References: <34E7B551.115C289F@cs.utexas.edu> <34E8AA02.7ED447E0@cs.utexas.edu> <34E91572.CE9CEED2@cs.utexas.edu> <34EB6579.C791152D@cs.utexas.edu> Organization: The Mitre Corp., Bedford, MA. Newsgroups: comp.lang.ada Date: 1998-03-05T00:00:00+00:00 List-Id: In article <34EB6579.C791152D@cs.utexas.edu> Yongxiang Gao writes (quoting Calvin): > Could you do another literature search for me? I'm interested in > papers that explain why Ada is an overly complex language, why it's > a hard language to write a compiler for, and other problems with Ada. Please remember in doing this search, to put the papers you get in context. For example, many of the criticisms of Ada 80 were directed at the IO model, which was completely redesigned for Ada 83. Yes, Ada 83 Text_IO took a lot of flack about the support for page numbering. But since IO was now completely an external package, rather than a built-in feature, no one had to use Text_IO if they didn't want to, and in fact, many compiler vendors provided--and still provide--a "Simple_IO" package which is faster and more suited for CRTs. Another criticism of Ada 83 was that it would be impossible to build a good compiler that ran on a machine with 128 K of memory. The third compiler validated did just that--although it was tough. However, for many years the R&R Compiler has fit nicely on a 640 K MS-DOS machine. The whole compiler, not just the programs created. And finally, there has been an incredibly long running criticism of the Ada (83) tasking model as overly complex. It may be, but it is also a COMPLETE tasking model that can serve as the tasking model underlying and exported by an operating system--and it a couple of cases it does. There are also many embedded real-time executives which support the Ada tasking model directly. In fact, much of the work on hard deadline scheduling has been done around Ada 83, and Ada 95 now includes support for additional scheduling models and allows adding others. Certainly a feature which maybe one Ada programmer in a hundred needs--but having it in the language means that most of the programmers on a large project never need to know it is there. -- Robert I. Eachus with Standard_Disclaimer; use Standard_Disclaimer; function Message (Text: in Clever_Ideas) return Better_Ideas is...