Andrew Davison

``` $ scryer-prolog ?- use_module(library(freeze)). true. ?- freeze(W,write('ok')). freeze:freeze(W,write(ok)). ?- freeze(W,write('ok')), bb_put(key, W). thread 'main' panicked at src/machine/machine_state_impl.rs:70:26: index out of bounds: the len is 82173 but the index is...

Can't retract imported dynamic predicate

1

``` $ cat m.pl :- module(m, [foo/0]). :- dynamic(foo/0). foo. $ scryer-prolog ?- use_module('m.pl'). true. ?- foo. true. ?- retractall(foo). error(permission_error(modify,static_procedure,foo/0),retract/1). ?- retractall(m:foo). true. ?- ``` Yap agrees with Scryer...

Problem with soft-if-then-else

1

> > I don't know if you like it but here is another discrepancy: (*->/2) > ``` > $ cat ite_3.pl > main :- > member(X,[true,\+true]), > ( member(X,[\+true,true,\+true]) *->...

Blackboard and attributes on a naked variable

3

This works... ``` $ swipl Welcome to SWI-Prolog (threaded, 64 bits, version 9.3.21-90-ge96c60c-DIRTY) ?- freeze(A,writeln(here)), nb_setval(abc, f(A)). freeze(A, writeln(here)). ?- b_getval(abc,A). A = f(_A), freeze(_A, writeln(here)). ?- b_getval(abc,A), A=f(123). here...

It seems foldl/6 is missing from lists.pl (as per Prologue to Prolog)

3

Only foldl/4-5 is provided and foldl/6 is depleted. Forgive the trivialness... on a par with the maplist/9 surfeit.

time/1 and extra output at top-level

3

Forgive the trivialness of this: ``` $ scryer-prolog -g "true,halt" $ vs. $ scryer-prolog -g "time(true),halt" % CPU time: 0.000s, 84 inferences $ ``` It's annoying because the extra spaces...