Learn Prolog now 9.2 introduces the list constructors . and [] and gives some example code :
?- .(a,[]) == [a]. yes
In SWI Prolog 7, this example gives the error
ERROR: Stream user_input:25:1 Syntax error: Unexpected end of clause
After googling, I found the reason: http://www.complang.tuwien.ac.at/ulrich/iso-prolog/SWI7_and_ISO. SWI7 deviates from the Prolog standard a bit as it seems. The workaround in SWI 7 is using [|], such as: ?- [a|[]]==[a].
(please see SWI documentation). Maybe you should add an explanatory message to the LPN mentioned above.
Learn Prolog now 9.2 introduces the list constructors . and [] and gives some example code :
?- .(a,[]) == [a]. yesIn SWI Prolog 7, this example gives the error
After googling, I found the reason: http://www.complang.tuwien.ac.at/ulrich/iso-prolog/SWI7_and_ISO. SWI7 deviates from the Prolog standard a bit as it seems. The workaround in SWI 7 is using [|], such as:
?- [a|[]]==[a].(please see SWI documentation). Maybe you should add an explanatory message to the LPN mentioned above.