Re: What I like about programming . . .

From	David Brown <david.brown@hesbynett.no>
Newsgroups	comp.programming
Subject	Re: What I like about programming . . .
Date	2023-02-09 09:42 +0100
Organization	A noiseless patient Spider
Message-ID	<ts2ble$kc4k$1@dont-email.me> (permalink)
References	(3 earlier) <ts0gci$4dtt$1@dont-email.me> <87cz6jlvd6.fsf@bsb.me.uk> <ts15r2$bfus$1@dont-email.me> <87lel7k5k9.fsf@bsb.me.uk> <ts26o6$jn1b$1@dont-email.me>

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On 09/02/2023 08:18, Richard Heathfield wrote:
> On 09/02/2023 1:09 am, Ben Bacarisse wrote:
>> Richard Heathfield <rjh@cpax.org.uk> writes:
>>

>>> If executed, the specified program will halt.
>>>
>>> Which it will. ALL programs halt.
>>
>> Come on!  You know I know what that C program does.
> 
> Yes, of course.
> 
>> What I don't know
>> is in what way that C program refutes a mathematical theorem.  One makes
>> statement about programs,
> 
> Yes. That statement refutes the mathematical theorem by pointing out an 
> obvious fact about all 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?
> 
> Of course all Turing machines halt. You don't seriously think it is 
> possible for a Turing machine *not* to halt, do you?
> 

You are making up new definitions here for pretty much all of the terms.

In the mathematics of computation and computability, where the halting 
problem and associated theorems live, some programs (or Turing machines) 
halt and some do not.

/Real-world/ programs always halt.  Most of the programs I write have an 
"infinite loop" - "while (true) { .... }" in them.  But they stop when 
someone switches off the board they are running on.  Even the last of 
the Novel Netware servers will stop with the heat death of the universe.

You /could/ argue that non-halting programs are just mathematical 
fantasies.  But like the infinite decimal expansion of pi, or the 
never-ending list of integers, they are very useful fantasies that let 
people reason about all kinds of /real/ things.

So let's please stick to the normal definitions of the terms, and not 
add hidden assumptions about real-world limitations to simple 
mathematical concepts.

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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

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