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,FREEMAIL_FROM
	autolearn=ham autolearn_force=no version=3.4.4
X-Google-Thread: 103376,ab1d177a5a26577d
X-Google-NewGroupId: yes
X-Google-Attributes: gida07f3367d7,domainid0,public,usenet
X-Google-Language: ENGLISH,UTF8
Received: by 10.68.8.135 with SMTP id r7mr8967919pba.8.1317762022240;
        Tue, 04 Oct 2011 14:00:22 -0700 (PDT)
Path: 
 lh7ni11606pbb.0!nntp.google.com!news1.google.com!goblin3!goblin1!goblin2!goblin.stu.neva.ru!aioe.org!.POSTED!not-for-mail
From: =?utf-8?Q?Yannick_Duch=C3=AAne_=28Hibou57?=
 =?utf-8?Q?=29?=
 <yannick_duchene@yahoo.fr>
Newsgroups: comp.lang.ada
Subject: Re: What's wrong with C++?
Date: Tue, 04 Oct 2011 23:00:20 +0200
Organization: Ada @ Home
Message-ID: <op.v2uhyugyule2fv@index.ici>
References: 
 <1ee1a434-4048-48f6-9f5e-d8126bebb808@r19g2000prm.googlegroups.com>
 <op.v2uhj3r7ule2fv@index.ici>
NNTP-Posting-Host: zr8m5dsiG+Rs6FWy4ndNjg.user.speranza.aioe.org
Mime-Version: 1.0
X-Complaints-To: abuse@aioe.org
User-Agent: Opera Mail/11.51 (Linux)
X-Notice: Filtered by postfilter v. 0.8.2
Xref: news1.google.com comp.lang.ada:18301
Content-Type: text/plain; charset=utf-8; format=flowed; delsp=yes
Content-Transfer-Encoding: Quoted-Printable
Date: 2011-10-04T23:00:20+02:00
List-Id: <comp.lang.ada>

Le Tue, 04 Oct 2011 22:51:29 +0200, Yannick Duch=C3=AAne (Hibou57)  =

<yannick_duchene@yahoo.fr> a =C3=A9crit:
> Here is an easy to read interesting answer to that question, from a C+=
+  =

> user, reporting about a C++ conference he attended to.
>
> http://cpptruths.blogspot.com/2005/10/whats-wrong-with-c.html

Quoted from a comment in the above link

> "One of the big issues was the extreme difficulty of parsing C++."
>
> It is ___provably___ impossible to write a correct C++ parser which
> will complete compilation with either success of failure because the
> C++ template system is Turing complete. This means that code generatio=
n
> is based on a turing complete program. Code generation in C++ isn't
> based on a program description, but an actual turing complete program.=

>
> As such, it is subject to the halting problem. Therefore, it is
> unknowable whether a compilation will complete, and unknowable if
> you are looking at a valid C++ program.

So OK, it is formally proved that is not even sure a given C++ source fi=
le  =

can really be compiled or not. That's big, ouch.

That achieve to prove that along with the domain troubles and  =

difficulties, you are also in as great troubles with the source it self.=


May be C++ would need to go beyond of Ada SPARK or Ada design by contrac=
t  =

(tm), and add stuff to prove a C++ source is correct and can be compiled=
,  =

before any attempt to prove what it will compiled is correct (oops).


-- =

=E2=80=9CSyntactic sugar causes cancer of the semi-colons.=E2=80=9D  [Ep=
igrams on  =

Programming =E2=80=94 Alan J. =E2=80=94 P. Yale University]
=E2=80=9CStructured Programming supports the law of the excluded muddle.=
=E2=80=9D [Idem]
Java: Write once, Never revisit