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: 103376,5697899e4423465c X-Google-Attributes: gid103376,public From: dewarr@my-dejanews.com Subject: Re: Boolean Representation Date: 1998/09/27 Message-ID: <6uli4d$mb9$1@nnrp1.dejanews.com>#1/1 X-Deja-AN: 395311131 References: X-Http-Proxy: 1.0 x3.dejanews.com:80 (Squid/1.1.22) for client 209.73.133.253 Organization: Deja News - The Leader in Internet Discussion X-Article-Creation-Date: Sun Sep 27 14:29:33 1998 GMT Newsgroups: comp.lang.ada X-Http-User-Agent: Mozilla/2.02 (OS/2; I) Date: 1998-09-27T00:00:00+00:00 List-Id: In article , stt@houdini.camb.inmet.com (Tucker Taft) wrote: > It is just this kind of thinking which led people to put "reconfirming" > representation clauses on enumeration types in Ada 83. What a waste > of energy! We added a rule in Ada 95 to save the paranoid from > writing all those silly enumeration representation clauses. I can > see we should have gone one step further, specifying the representation > for 1-bit boolean objects. Groan. No, I don't think such a rule is necessary, it is clearly the intention of the RM that one bit boolean representations are like all other enumeration representations in that the representations must be ordered. Remember that when you read the RM, just because you manage to find a reading that confirms something absurd does not mean that Ada allows absurd things. After all, any possible reading of the Ada 83 RM that is done in this uninformed style will tell you that virtually no subtypes are static, e.g. subtype x is integer range 1 .. 10; is not a static subtype. But this never actually bothered anyone, except the ARG who had to waste a few minutes fixing the RM for the record. I am not even sure that this particular issue (one bit boolean must have rep 0/1) needs an AI. If it does, fine the ARG will issue one, but like many many AI's this AI will have absolutely zero impact on any real user of Ada unless they fail to understand the dynamics of the language definition. After all, remember that there is nothing in the RM to stop an implementation from using a loop with serial addition to implement multiplication, but even the paranoid among Ada users do not eschew multiplication because of this. You have to have some sense of the reasonable when using any language! Even if you have a formal definition of a language, there can be errors in the definition. If a typo in the formal definition ends up resulting in an implication that "<" means ">" all this means is that there is an error in the formal definition, not in the language being defined! -----== Posted via Deja News, The Leader in Internet Discussion ==----- http://www.dejanews.com/rg_mkgrp.xp Create Your Own Free Member Forum