Eval's are indeed less performatic than any other type of constraints.
"inline-evals" are not as bad, but are also heavier than regular
constraints.
  The recommendation is to avoid when possible, but for some cases it is
not possible.

  If you are using MR3 or later, you can use MVELs syntax in your
constraints:

when
  MyClass( aMapAttribute['aKey'] == "some Value" )
then
  ...
end

   The above will transparently be translated to an inline-eval, but that
is the best you can do when working with maps.

   []s
   Edson


2007/7/2, Rajesh_Kumar <[EMAIL PROTECTED]>:

Hi all,

I want to use "eval" in my rules, but in rule writing guidelines Mark
has
Written that "Eval is Evil".

I want to compare the values of Hash Map in my when (conditions) part.

1) Will anyone suggest something so that I can compare Hash Map keys in
when part?

2) Does is there any performance related issue related to "eval";

Regards

Rajesh

--
This message has been scanned for viruses and
dangerous content by MailScanner, and is
believed to be clean.


_______________________________________________
rules-users mailing list
[email protected]
https://lists.jboss.org/mailman/listinfo/rules-users




--
 Edson Tirelli
 Software Engineer - JBoss Rules Core Developer
 Office: +55 11 3529-6000
 Mobile: +55 11 9287-5646
 JBoss, a division of Red Hat @ www.jboss.com
_______________________________________________
rules-users mailing list
[email protected]
https://lists.jboss.org/mailman/listinfo/rules-users

Reply via email to