heh, I made a mistake
with the rule
( Location(z, y;) and ?hasFood(x, z;) )
should be
( Location(z, y;) and hasFood(x, z;) )
Otherwise it's not reactive, and then ordering
matters.
With that change I can do the insertions in any
order and all is fine.
This works for the example you gave. But the one
taken from the "Introduction" still depends on the
order the facts are inserted. Below is the .drl,
which does not need any pojos. Rule kickOff
contains the order that produces nothing to see
and eat:
You are in the table
You can see []
You can eat []
Insert Here after the others, and it works.
-W
import java.util.List
declare Thing
thing : String @key
end
declare Edible extends Thing
end
declare Location extends Thing
location : String @key
end
declare Here
place : String
end
rule kickOff
when
then
System.out.println( "insert Here" );
insert( new Here( "table" ) );
System.out.println( "insert Edible" );
insert( new Edible( "peach" ) );
System.out.println( "insert Location" );
insert( new Location( "peach", "table" ) );
end
# 2011-06-22
query isContainedIn( String x, String y )
Location(x, y;)
or
( Location(z, y;) and /*?*/isContainedIn(x,
z;) )
end
query whereFood( String x, String y )
( Location(x, y;) and
Edible(x;) )
or
( Location(z, y;) and /*?*/whereFood(x, z;) )
end
query look(String place, List things, List food)
Here(place;)
things := List() from accumulate(
Location(thing, place;),
collectList(
thing ) )
food := List() from accumulate(
/*?*/whereFood(thing, place;),
collectList(
thing ) )
end
rule reactiveLook
when
Here( $place : place)
/*?*/look($place, $things; $food := food)
then
System.out.println( "You are in the " +
$place);
System.out.println( " You can see " + $things
);
System.out.println( " You can eat " + $food
);
end