Re: Prologs with Occurs Check constantly on?

Jan Wielemaker schrieb:
I may hope not. On this example, hanging or crashing systems are ISO
compliant, but I sincerely hope we left this era behind us.

Cheers --- Jan

Goody, goody. Made a little test, running Prolog systems
in default mode (so not explicitly fidling with the occurs
check flag):

?- X=f(X), Y=f(Y), X=Y.

SWI: Succeeds
SICStus: Succeeds
YAP: Succeeds
GNU: Hangs, reacts on ^C
B-Prolog: Hangs, does not react on ^C
Ciao: Memory allocation failed

50% in new era?

All 3 prologs that succeed show the resulting
cyclic terms in a different way...

Bye

.