Thanks, Oana. I think I’m finally starting
to get a grip on this thing J.
Vlad
From:
rules-users-bounces@lists.jboss.org
[mailto:rules-users-bounces@lists.jboss.org] On
Behalf Of nicolae oana
Sent: 20 February 2007 03:38
To:
Subject: Re: [rules-users] exists
+ normal column constraints - how many times a rule is cal led in the end????
Vlad,
exists Person(role == "parent")
checks if in workingMemory is at least one Person fact having attribute
role == "parent", in both your examples.
Your reasoning is correct: the four facts with role =="child" will
activate the rule. So, the result for your second example will be the same as
the first result, for your list of facts, no matter how you switch the columns.
Regards,
Oana
"Olenin, Vladimir
(MOH)" <Vladimir.Olenin@moh.gov.on.ca> wrote:
Hi,
I’m not sure my understanding
of ‘existential quantifiers’ is correct. Hopefully, someone can
clear it up a bit…
Providing I have the following fact
class:
Person(role: parent/child, name)
And following facts:
1: parent, John
2: parent, Alice
3: parent, Steve
4: parent, Jane
5: child, Eric
6: child, Rob
7: child, May
8: child, April
I expect the rule
Rule “iterate children if at
least one parent is found”
When
exists Person(role == ‘parent’)
$child: Person(role == ‘child’)
Then
// do smth for each $child if at least one parent is found
End
To iterate through all
‘child’ persons (facts 5 through 8), ie the action will be called
exactly 4 times. Is this correct? What would happen if I swap the order of the
conditions (with ‘parent exists’ constrain going _after_ ‘child’ constraint):
When
$child: Person(role == ‘child’)
exists Person(role == ‘parent’)
Thanks,
Vlad
_______________________________________________
rules-users mailing list
rules-users@lists.jboss.org
https://lists.jboss.org/mailman/listinfo/rules-users
Now that's room service! Choose
from over 150,000 hotels
in 45,000 destinations on Yahoo! Travel to find your fit.