Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > comp.programming > #16384

Re: What I like about programming . . .

Show key headers only | View raw

Richard Heathfield <rjh@cpax.org.uk> writes:

> On 08/02/2023 9:07 pm, Ben Bacarisse wrote:
>> Richard Heathfield <rjh@cpax.org.uk> writes:
>> 
>>> On 08/02/2023 3:03 pm, Paul N wrote:
>>>> On Tuesday, February 7, 2023 at 9:58:29 PM UTC, JJ wrote:
>>>>> If you go to any programming sub in Reddit, or any programming channel in
>>>>> Discord, you'll realize that some people aren't capable of realizing that
>>>>> they are wrong.
>> Yes, it's a rather quaint idea.  Some subjects might make it easier for
>> people with open minds to discover their mistakes, but it's very far
>> from being universal!
>
> Indeed, although computer programs have proven to be singularly adept at
> proving their authors wrong!

Yes, that's a good point.  Programming is more frequently humbling than
very many other activities, at least for most of us.

>>>> This is even more obvious in comp.theory. There is a poster there who
>>>> claims to have refuted the Halting Problem proof,
>>>
>>> I refute it too. Bear with me.
>> OK...
>
> Ta.
>
>>>> and to have a system which can accurately determine whether a program
>>>> will halt or not.
>>>
>>> I, too, have such a system. Bear with me.
>> This is a rather different claim.  The "Halting Problem proof" surely
>> refers to a proof of a specific mathematical theorem, so it's not clear
>> in what way any particular C program refutes it.
>
> The refutation is in the program's output (which is always correct):
>
> If executed, the specified program will halt.
>
> Which it will. ALL programs halt.

Come on!  You know I know what that C program does.  What I don't know
is in what way that C program refutes a mathematical theorem.  One makes
statement about programs, the other makes statements are Turing
machines.  Presumably you don't think Turing machines all halt in the
same sense that you think all programs halt?

>>>> He has a demonstration program, which he claims does not halt
>> His claims change, but when I last checked in he (the loon in
>> comp.theory) was still being clear that the program in question halts.
>> He's posted code, he's posted traces of the simulation, he's stated it
>> in plain words.
>> 
>>> He is mistaken.
>> On this point, no.
>
> The specific statement I was addressing was: "He has a demonstration
> program, which he claims does not halt"
>
> Such a claim would be erroneous.

OK.  I was addressing his claims in the context of his model of
computation, not yours.  His is abstract, yours is concrete.  The
abstract model is interesting whereas yours is not -- in the technical
sense of interesting (that has been cut).

<cut>
>>>> He does however accept that when said program is run, it halts.
>> Just to clear up the nonsense he spouts, he claims that "non-halting" is
>> the right answer because of what /would/ happen if the program were not
>> stopped -- that the program in question only halts because it is stopped
>> "by itself".  Yes, it's bonkers, but he maintains he's right because
>> he's changed what "halting" means.
>
> We all know what "halting" means, and we all should know that all programs
> halt.

Words rarely have unique meanings across all contexts.  Halting means
all sorts of things.  I'm forever halting my dog during a walk, and then
calling "walk on".  I used to use a button to halt a program on a
mainframe when I needed to do certain physical activities with it.  It
would then resume from halting.

Yes, we /should/ all know what halting, in the context of a "problem" in
computer science, means and I would imagine that you do too, but I keep
making the mistake of thinking that it's worth making technical replies
to humorous posts.

> <snip>

Oh, OK.

>> OK, /I/ know you are joking, but will everyone?
>
> No. That's part of the joy of Usenet.
>
>> Do we want any more
>> people confused about what the halting theorem is about?
>
> Interesting exercise: attempt to justify a "yes" answer in an entertaining
> way. (I came up with three that are far too dull to post.)

I'm old-school.  I liked it more when Usenet was informative rather than
entertaining.  I prefer to learn what people know and think and believe
about things.  I'll try to reply in a more entertaining way in future!

-- 
Ben.

Back to comp.programming | Previous | Next — Previous in thread | Next in thread | Find similar

Thread

Re: What I like about programming  . . . JJ <jj4public@outlook.com> - 2023-02-08 04:58 +0700
  Re: What I like about programming . . . David Brown <david.brown@hesbynett.no> - 2023-02-08 08:59 +0100
  Re: What I like about programming . . . Richard Heathfield <rjh@cpax.org.uk> - 2023-02-08 09:34 +0000
  Re: What I like about programming . . . Paul N <gw7rib@aol.com> - 2023-02-08 07:03 -0800
    Re: What I like about programming . . . Richard Heathfield <rjh@cpax.org.uk> - 2023-02-08 15:50 +0000
      Re: What I like about programming . . . Ben Bacarisse <ben.usenet@bsb.me.uk> - 2023-02-08 21:07 +0000
        Re: What I like about programming . . . Richard Heathfield <rjh@cpax.org.uk> - 2023-02-08 21:56 +0000
          Re: What I like about programming . . . Ben Bacarisse <ben.usenet@bsb.me.uk> - 2023-02-09 01:09 +0000
            Re: What I like about programming . . . Richard Heathfield <rjh@cpax.org.uk> - 2023-02-09 07:18 +0000
              Re: What I like about programming . . . David Brown <david.brown@hesbynett.no> - 2023-02-09 09:42 +0100
                Re: What I like about programming . . . "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de> - 2023-02-09 11:17 +0100
                Re: What I like about programming . . . David Brown <david.brown@hesbynett.no> - 2023-02-09 14:15 +0100
                Re: What I like about programming . . . Richard Heathfield <rjh@cpax.org.uk> - 2023-02-09 11:41 +0000
                Re: What I like about programming . . . David Brown <david.brown@hesbynett.no> - 2023-02-09 14:20 +0100
                Re: What I like about programming . . . Richard Heathfield <rjh@cpax.org.uk> - 2023-02-09 13:38 +0000
              Re: What I like about programming . . . Ben Bacarisse <ben.usenet@bsb.me.uk> - 2023-02-09 14:05 +0000
                Re: What I like about programming . . . Richard Heathfield <rjh@cpax.org.uk> - 2023-02-10 07:04 +0000
                Re: What I like about programming . . . Ben Bacarisse <ben.usenet@bsb.me.uk> - 2023-02-10 11:46 +0000
                Re: What I like about programming . . . Richard Heathfield <rjh@cpax.org.uk> - 2023-02-10 12:49 +0000
                Re: What I like about programming . . . Y A <air000000000000@ya.ee> - 2023-02-10 06:37 -0800
                Re: What I like about programming . . . Ben Bacarisse <ben.usenet@bsb.me.uk> - 2023-02-10 23:16 +0000
                Re: What I like about programming . . . Richard Heathfield <rjh@cpax.org.uk> - 2023-02-11 07:20 +0000
                Re: What I like about programming . . . Ben Bacarisse <ben.usenet@bsb.me.uk> - 2023-02-11 21:12 +0000
                Re: What I like about programming . . . Richard Heathfield <rjh@cpax.org.uk> - 2023-02-11 23:05 +0000

csiph-web