Help Can't execute XPCE?

Hello, I’m new with Swi-Prolog and XPCE,
My pb is I failed many times to execute some exemple as graphical window example ( from Swi-Prolog page tutorials),
SWP gave me many errors as “Syntax error: Operator expected” ?
I noticed that it happens when I used tutorial exemple with “@” prefix operator (?) Inside it.
I Dont know if I miss something somewhere ?
Thanks for your help.

Jeangil

Here I put a copy of my screen after execution :

"Welcome to SWI-Prolog (threaded, 64 bits, version 8.0.3)
SWI-Prolog comes with ABSOLUTELY NO WARRANTY. This is free software.
Please run ?- license. for legal details.

For online help and background, visit http://www.swi-prolog.org
For built-in help, use ?- help(Topic). or ?- apropos(Word).

?- new(X, picture).
X = @10174570/picture.

?- send(@10174570, open(point(200,200))).
ERROR: Syntax error: Operator expected
ERROR: send(
ERROR: ** here **
ERROR: @10174570, open(point(200,200))) .
?-

Once upon a time XPCE was an unseperable part of SWI-Prolog. Nowadays it is a not so often used library. To get the operators, load library(pce). In a program that means

:- use_module(library(pce).

Interacttive you can use ?- [library(pce)]. If you start it from the commandline, recent versions can also use swipl --pce.

Thanks a lot Jan,
now it’s working !!

Regards

Jeangil