Path: utzoo!attcan!uunet!husc6!bu-cs!buengc!art
From: art@buengc.BU.EDU (A. R. Thompson)
Newsgroups: comp.lang.pascal
Subject: Re: Control variables in FOR loops
Message-ID: <1806@buengc.BU.EDU>
Date: 28 Dec 88 23:16:31 GMT
References: <1439@csuna.UUCP> <45@csd4.milw.wisc.edu> <1771@buengc.BU.EDU> <3693@s.cc.purdue.edu> <1804@buengc.BU.EDU>
Reply-To: art@buengc.bu.edu (A. R. Thompson)
Followup-To: comp.lang.pascal
Organization: Boston Univ. Col. of Eng.
Lines: 38

Hi Al!

I read comp.lang.pascal, but presently can't respond directly.

I just noticed the following:

-----------------------------------

In article <3693@s.cc.purdue.edu> ags@s.cc.purdue.edu (Dave Seaman) writes:
>In article <1771@buengc.BU.EDU> art@buengc.bu.edu (A. R. Thompson) writes:
>>Ah, but since you've already established that it's an illegal program you
>>can no longer predict what will happen.  That's strictly up to the
>>compiler writer (who is duty bound to report the error and refuse to
>>generate executable code).
>
>Not so.  The compiler writer is free to do whatever he likes, provided the
>accompanying documentation describes the types of errors that are not
>reported by the compiler.
>

While the standard may allow this I take exception to it in cases like
this.

-----------------------------------

In fact, the compiler writer is NOT "free to do whatever he likes" if she
is writing a standards-conforming compiler.  Most of the restrictions under
discussion are not "errors" (as defined in the standard), and thus a
conforming processor (compiler) MUST detect violations of those
restrictions.  It is only those restrictions explicitly defined by the
standard as "errors" or "implementation-dependent" for which detection is
optional.

Please forward this to the net.

Regards,

Jim Miner