From Newsgroup: comp.lang.prolog

Hi,

Now that we managed to conceive nested arrow
functions, next step on the menu is inner if-then-else
or disjunction, like inside a findall/3 or inside

(\+)/1, doing ahead of time compilation (AOT).
That it leads to problems of rational trees was
more a psyop easter egg of mine. Although I am not

yet sure, in the long run the compiler should
be able to handle rational trees, like copy_term/2
can handle them. But before tackling inner

if-then-else, first check the occurence frequency
of then. Do they happen often? Is it worth AOT-ing
them. Then also before tackling inner if-then-else,

does the code use (,)/2, (;)/2 or (->)/2 in
scenarios where it is used for meta programming
i.e. _,_, _;_ or _->_ pattern for deconstruction

or construction. And do these cases fall into
the new arrow viability check adopte to a if-then-else
viability check, or fall they through?

Bye

Mild Shock schrieb:

Hi,

Functional requirement:

?- Y = g(_,_), X = f(Y,C,D,Y), term_singletons(X, L),
   L == [C,D].

?- Y = g(A,X,B), X = f(Y,C,D), term_singletons(X, L),
   L == [A,B,C,D].

Non-Functional requirement:

?- member(N,[5,10,15]), time(singletons(N)), fail; true.
% Zeit 1 ms, GC 0 ms, Lips 4046000, Uhr 11.08.2025 01:36
% Zeit 3 ms, GC 0 ms, Lips 1352000, Uhr 11.08.2025 01:36
% Zeit 3 ms, GC 0 ms, Lips 1355333, Uhr 11.08.2025 01:36
true.

Can your Prolog system do that?

P.S.: Benchmark was:

singletons(N) :-
   hydra2(N,Y),
   between(1,1000,_), term_singletons(Y,_), fail; true.

hydra2(0, _) :- !.
hydra2(N, s(X,X)) :-
   M is N-1,
   hydra2(M, X).

Bye

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From Newsgroup: comp.lang.prolog

Hi,

Credits go to myself (an old Stackoverflow
post of mine from 2020):

The algorithm "A" according to Antoni Diller looks fairly simple: https://stackoverflow.com/questions/65066544/bracket-abstraction-in-prolog

The OrReference aka Anonymous Predicate is just another variant
of combinatorial logic. You can view OrReference having the same
logtical status as a closed SKI expression.

Plus to this guys here also already in 2004:

Hiord: A Type-Free Higher-Order Logic Programming
Language with Predicate Abstraction
Daniel Cabeza, Manuel V. Hermenegildo, Manuel V. Hermenegildo https://www.researchgate.net/publication/221052995

Only they botched it, since recursion and mutual recursion
needs still some fixpoint operator construction. But
the Anonymous Predicate thingy is beautiful, without

any fixpoint operator construction needed:

test(Even) :-
Even = ((X) => Y^(X = n; X = s(Y), call(Odd, Y))),
Odd = ((X) => Y^(X = s(Y), call(Even, Y))).

?- listing(test).
test(A) :-
A = 0rReference(B),
B = 0rReference(A).

Basically evaluating a rational tree closure:

?- test(_X), call(_X, s(s(s(s(n))))).
true.

?- test(_X), call(_X, s(s(s(s(s(n)))))).
fail.

?- test(_X), call(_X, s(s(s(s(s(s(n))))))).
true.

Bye

Mild Shock schrieb:

Hi,

Now that we managed to conceive nested arrow
functions, next step on the menu is inner if-then-else
or disjunction, like inside a findall/3 or inside

(\+)/1, doing ahead of time compilation (AOT).
That it leads to problems of rational trees was
more a psyop easter egg of mine. Although I am not

yet sure, in the long run the compiler should
be able to handle rational trees, like copy_term/2
can handle them. But before tackling inner

if-then-else, first check the occurence frequency
of then. Do they happen often? Is it worth AOT-ing
them. Then also before tackling inner if-then-else,

does the code use (,)/2, (;)/2 or (->)/2 in
scenarios where it is used for meta programming
i.e. _,_, _;_ or _->_ pattern for deconstruction

or construction. And do these cases fall into
the new arrow viability check adopte to a if-then-else
viability check, or fall they through?

Bye

Mild Shock schrieb:

Hi,

Functional requirement:

?- Y = g(_,_), X = f(Y,C,D,Y), term_singletons(X, L),
    L == [C,D].

?- Y = g(A,X,B), X = f(Y,C,D), term_singletons(X, L),
    L == [A,B,C,D].

Non-Functional requirement:

?- member(N,[5,10,15]), time(singletons(N)), fail; true.
% Zeit 1 ms, GC 0 ms, Lips 4046000, Uhr 11.08.2025 01:36
% Zeit 3 ms, GC 0 ms, Lips 1352000, Uhr 11.08.2025 01:36
% Zeit 3 ms, GC 0 ms, Lips 1355333, Uhr 11.08.2025 01:36
true.

Can your Prolog system do that?

P.S.: Benchmark was:

singletons(N) :-
    hydra2(N,Y),
    between(1,1000,_), term_singletons(Y,_), fail; true.

hydra2(0, _) :- !.
hydra2(N, s(X,X)) :-
    M is N-1,
    hydra2(M, X).

Bye

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