SWI-Prolog -- pce

pce_global(+Ref, +Pred)

Declare a predicate that creates the object referred to as Ref. Part of XPCE's facility to create objects only when they are actually needed: this keeps start-up time short for large applications.

The first argument is the global reference being declared. The second is either the name of a predicate capable of creating the object, or a term wrapped in new/1 representing the object.

Examples:

:- pce_global(@center,
              new(spatial(xref = x+w/2, yref = y+h/2,
                          xref = x+w/2, yref = y+h/2))).

:- pce_global(@pce_icon, make_pce_icon).

make_pce_icon(Ref) :-
    new(Ref, bitmap),
    send(Ref, load, 'pce.bm').