UWN
``` ?- [user]. p :- X #< Y, X #> Y. ?- p. true. ?- call_residue_vars(p, Vs). Vs = [_B], clpz:(_A#=
``` ?- length(L,11). L = [_A,_B,_C,_D,_E,_F,_G,_H,_I,_J|...]. % OK ?- X = "abcdefghijklmnopqrstuvwxyz". X = "abcdefghijklmnopqrs ...". ``` Much more should be printed! At least 4 times the size of the...
[#1](http://www.complang.tuwien.ac.at/ulrich/iso-prolog/variable_names#1)
``` :- dynamic(r//0). r,_ --> []. ?- R=(H:-B), H = r(S0,S), clause(H,B). R = (r(S0,S):-S0=_A,S=_A), H = r(S0,S), B = (S0=_A,S=_A), unexpected. ?- [R,S0,S]+\ ( R=(H:-B), H = r(S0,S), clause(H,B)...
``` ulrich@p0:~$ ulimit -v 250000 ulrich@p0:~$ /opt/gupu/scryer-prolog/target/release/scryer-prolog -f ?- repeat, call((G=(false,false),G)). memory allocation of 448 bytes failed Aborted (core dumped) ``` (This is on `p0` which is happy with less...
Instantiation errors do not produce much information. They just say: More instantiation is needed. But type errors are (declaratively) tantamount to failure. So in case it is easy to prefer...
Many directives that accept predicate indicators (7.1.6.6) also accept a predicate indicator sequence (7.1.6.7) and a predicate indicator list (7.1.6.8). Namely, `dynamic/1` (7.4.2.1), `multifile/1` (7.4.2.2), `discontiguous/1` (7.4.2.3). Instead, Scryer displays...
``` ?- [user]. a. b. a. Warning: overwriting a/0 ``` Rather: Warning: overwriting a/0 because clauses are discontiguous
``` ?- number_chars(N,"0' "). error(syntax_error(unexpected_char),number_chars/2:0), unexpected. syntax_error(_), unexpected. N = 32. % expected in ASCII, Unicode ```
``` ?- [user]. p([X,Y]) :- dif(X,Y). p([X,Y]) :- dif(Y,X). ?- p(Xs). Xs = [_A,_B], dif:dif(_A,_B) ; Xs = [_B,_A], dif:dif(_A,_B), unexpected. % odd naming % expected results: Xs = [_A,_B],...