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

Groups > comp.lang.prolog > #14789

Entering the Age of Rational Trees (2025) (Was: The End of Deutsch-Schorr-Waite [cycle_detection.rs])

Show all headers | View raw

 > I like your vibe, clearing the mind of
 > everything existing has a touch of a mystic
 > human being living an eremitic solitary
 > vocation on a far out mountain top.

It is not accidential that there is a resemblage
to the ivory tower of academics. Which might create
incestual orthodoxical knowledge, with very less value.

Prolog systems development is especially susceptible
to this fallacy, since it has a long tradition
going always the same paths, like WAM, etc.. etc..

The pointer swizzling algorithms of SWI-Prolog,
in connection with cyclic terms are a little
problematic. What if a Prolog term sits in a

read-only memory, or is shared among multiple threads.
How do you do pointer swizzling of ROM and not RAM?
We might indeed see the The End of Deutsch-Schorr-Waite,

although it made it still into Scryer Prolog:

 > **cycle_detection.rs**
Use the pointer reversal technique of the Deutsch-Schorr-
Waite algorithm to detect cycles in Prolog terms.
https://github.com/mthom/scryer-prolog/blob/master/src/machine/cycle_detection.rs

To enter the age of rational trees, it is probably
advisable to arm oneself not only with Fuzzy Testing,
but unlike the dislike of @kuniaki.mukai , one needs

to probably also study all the goodies from 1970's
computer science. But add a salt of scepticism, since
hardware and programming languages look different now.

Its not ALGOL anymore.

Mild Shock schrieb:
> Hi,
> 
> Assume that we live in a world where we
> have excess memory. So we can afford stacks!
> And then make the crucial observation,
> 
> we can use the stack of the Prolog engine,
> no need to create an artificial stack in C,
> or use the native stack of C.
> 
> I guess SWI-Prolog has already groked the
> first we can "afford stacks". But did anybody
> already grok the "100% Prolog" idea?
> 
> Well we are not yet there 100% Prolog
> has still an overhead. Here is a little
> test acyclic_term/2:
> 
> /* SWI-Prolog 9.3.26, C Stacks and/or Agendas */
> ?- time((between(1,30,_), acyclic2, fail; true)).
> % 330,150 inferences, 0.016 CPU in 0.023 seconds
> (69% CPU, 21129600 Lips)
> true.
> 
> /* Trealla Prolog 2.79.6, ?? */
> ?- time((between(1,30,_), acyclic2, fail; true)).
> % Time elapsed 0.063s, 643413 Inferences, 10.166 MLips
>     true.
> 
> /* Dogelog Player 1.3.5, 100% Prolog */
> ?- time((between(1,30,_), acyclic2, fail; true)).
> % Zeit 115 ms, GC 0 ms, Lips 11803904, Uhr 28.07.2025 10:03
> true.
> 
> /* Scryer Prolog 0.9.4-417, Deutsch-Schorr-Waite  */
> ?- time((between(1,30,_), acyclic2, fail; true)).
> % CPU time: 0.130s, 626_829 inferences
> true.
> 
> Bye

Back to comp.lang.prolog | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

Novacore goes Bisimulation: Scryer Prolog is Slow! Mild Shock <janburse@fastmail.fm> - 2025-07-25 13:51 +0200
  Is Mild Shock going rogue? (Was: Novacore goes Bisimulation: Scryer Prolog is Slow!) Mild Shock <janburse@fastmail.fm> - 2025-07-25 14:07 +0200
    Is Mostowski Collapse a professional mathematician (Was: Is Mild Shock going rogue?) Mild Shock <janburse@fastmail.fm> - 2025-07-25 14:16 +0200
      New Project Name: NovaCore becomes VibeCore (Re: Is Mostowski Collapse a professional mathematician) Mild Shock <janburse@fastmail.fm> - 2025-07-25 14:42 +0200
  Nice Printing Error Scryer Prolog (Was: Novacore goes Bisimulation: Scryer Prolog is Slow!) Mild Shock <janburse@fastmail.fm> - 2025-07-26 21:33 +0200
    Dynamic unify_with_occurs_check/2 speed-up (Was: Nice Printing Error Scryer Prolog) Mild Shock <janburse@fastmail.fm> - 2025-07-26 21:37 +0200
  The End of Deutsch-Schorr-Waite [cycle_detection.rs] (Was: Novacore goes Bisimulation: Scryer Prolog is Slow!) Mild Shock <janburse@fastmail.fm> - 2025-07-28 10:50 +0200
    Backtracking Branching Association List (Re: The End of Deutsch-Schorr-Waite [cycle_detection.rs]) Mild Shock <janburse@fastmail.fm> - 2025-07-28 11:02 +0200
      Do it like in acyclic_decompose/3 (Re: Backtracking Branching Association List) Mild Shock <janburse@fastmail.fm> - 2025-07-28 11:38 +0200
        Cache-Trashing vs Cache-Friendly [Code Example] (Re: Do it like in acyclic_decompose/3) Mild Shock <janburse@fastmail.fm> - 2025-07-28 17:27 +0200
    Entering the Age of Rational Trees (2025) (Was: The End of Deutsch-Schorr-Waite [cycle_detection.rs]) Mild Shock <janburse@fastmail.fm> - 2025-08-16 13:02 +0200
    The End of Debray Allocator (Was: The End of Deutsch-Schorr-Waite [cycle_detection.rs]) Mild Shock <janburse@fastmail.fm> - 2025-08-24 14:44 +0200
  The pairs are nasty, otherwise not always slow! (Re: Novacore goes Bisimulation: Scryer Prolog is Slow!) Mild Shock <janburse@fastmail.fm> - 2025-07-30 14:45 +0200
    It was painful for my GC, but fixed now (Re: The pairs are nasty, otherwise not always slow!) Mild Shock <janburse@fastmail.fm> - 2025-07-30 14:51 +0200
  Scryer Prolog has the most useless max_depth (Re: Novacore goes Bisimulation: Scryer Prolog is Slow!) Mild Shock <janburse@fastmail.fm> - 2025-08-02 13:43 +0200
    Novacore goes native (=)/2 and (==)/2 bisimulation (Was: Scryer Prolog has the most useless max_depth) Mild Shock <janburse@fastmail.fm> - 2025-08-02 14:45 +0200

csiph-web