Re: Incorrect requirements --- Computing the mapping from the input to HHH(DD)

On 11/05/2025 13:41, Mr Flibble wrote:

On Sun, 11 May 2025 13:36:47 +0100, Richard Heathfield wrote:
 

On 11/05/2025 13:17, Mr Flibble wrote:

On Sun, 11 May 2025 13:12:14 +0100, Richard Heathfield wrote:
>

On 11/05/2025 13:09, Mr Flibble wrote:

On Sun, 11 May 2025 12:57:21 +0100, Richard Heathfield wrote:
>

On 11/05/2025 12:48, Mr Flibble wrote:

On Sun, 11 May 2025 10:34:18 +0000, Alan Mackenzie wrote:
>

Mr Flibble <flibble@red-dwarf.jmc.corp> wrote:

>
<snip>
>

Nope, I have formally defined the error that doesn't contradict
Peter's work.

>
You don't even understand what "formally" means.

>
Sure I do. I can formally define it again for you if you like? Here
is the formal definition:
>
What constitutes halting problem pathological input:
>
Input that would cause infinite recursion when using a decider of
the simulating kind.

>
When executed directly, such an input would either halt or not,
category error or no.
>
Which is it?

>
Peter's view:
* direct execution results in infinite recursion which is treated as
non-
halting.
>
Flibble's view:
* direct execution results in manifestation of the category error:
which in practice means a crash in the form of a stack fault
(debatable halting equivalance) for a decider with finite resources
(stack space) or non- halting for a decider with infinitie resources
(stack space).

>
So what you're saying is that the pair of you can't decide.

>
What is that supposed to mean?
>
The infinite recursion is a manifestation of the category error; the
halting problem relies on two aspects: self-reference then
diagonalization but that latter can never happen as the former is
invalid.
>
>

QED.

>
All you have demonstrated is hand waving.

>
On the contrary, you described a category of decider program as
"pathological input" that demonstrated that the Halting Problem proof is
flawed.
>
The Halting Problem proof claims to prove that there are some programs
whose termination status we can't know. You have devised a program
category which you claim overturns this proof, and you claim that you
can even describe the behaviour of at least one program in this
category, but you... don't know its termination status.

 I have fully described its termination status, again:
 Flibble's view:
* direct execution results in manifestation of the category error:
which in practice means a crash in the form of a stack fault
(debatable halting equivalance) for a decider with finite resources
(stack space) or non- halting for a decider with infinitie resources
(stack space).

Nothing has infinite resources, so your vote is that it crashes, yes? And I think we have to count that as halting.

Peter's view:
* direct execution results in infinite recursion which is treated as non-
halting.

Non-halting.
One vote each - a tie.
So what you're saying is that the pair of you can't decide.
QED^2.
--
Richard Heathfield
Email: rjh at cpax dot org dot uk
"Usenet is a strange place" - dmr 29 July 1999
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