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: 103376,3498dd887729ed19 X-Google-Attributes: gid103376,public From: dewar@merv.cs.nyu.edu (Robert Dewar) Subject: Re: Garbage Collection in Ada Date: 1996/10/15 Message-ID: #1/1 X-Deja-AN: 189638718 references: <01bbb910$f1e73f60$829d6482@joy.ericsson.se> <199610132138291604607@dialup101-6-14.swipnet.se> <1996Oct13.194807.1@eisner> organization: New York University newsgroups: comp.lang.ada Date: 1996-10-15T00:00:00+00:00 List-Id: Jon Anthony says "A chicken or egg problem if there ever was one. I certainly could use GC in what I'm doing - I now have had to basically roll my own for the particular application. We don't have the $$ to actually fund such an effort - say in GNAT by ACT. Not alone that's for sure. But I would bet that there are quite a few such people out here who want it, but can't fund such an effort alone. I also know of many others that make the claim that lack of GC is about the only thing that keeps them from using Ada." Many people claim many things. One thing to be careful of is that people often justify not using Ada because Ada lacks xxx, and then rush off and use some other language that lacks xxx. In the case of GC, there are not many languages that in practice compete with Ada that supply GC, so I doubt these claims. If and when Java becomes a pratical vehicle for the kind of applications that might otherwise be written in Ada, this situation may change, but I suspect the claim above is valid. In particular, our experience is often that people making such claims don't even want to pay for *any* support, what they want is a version of GNAT they can use free that has the feature they want. That's a perfectly reasonable thing to want, but wanting does not make it so! Clearly any Ada company will fund developments that it thinks might interest potential customers. So far, we don't buy the argument that investing $x in implementing GC will increase our support income by $x (not to mention more than $x), so it's not on our list of priorities. There are many other items where we make the opposite judgment. Recent examples are the production of a PCS for distributed applications, and the full support of machine code insertions -- there are many others. You have to remember here that I am an enthusiastic supporter of the notion of garbage collection (see for example my paper in 1977 on an interesting new garbage collection algorithm used in the Macro-SPITBOL compilers in SOftware Practice and Experience). I am a little dubious about mixing GC with full Ada 95 (e.g. GC and unchecked conversion between integers and pointers are not friends), but certainly GC with a slightly restricted Ada 95 semantics is perfectly practical, and you can add me to the people who would like to see it (but are not willing to sign a big check for it!) Robert Dewar