<br> Is your inline eval() time-constant? I would guess that "howOld()" is returning different values when executed at different times. Inline evals MUST be time-constant. Top level evals can deal with non-time-constant expressions.<br>
<br> []s<br> Edson<br><br><div class="gmail_quote">2008/12/10 Bagwell, Allen F <span dir="ltr"><<a href="mailto:afbagwe@sandia.gov">afbagwe@sandia.gov</a>></span><br><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
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<div><font size="2">I'm puzzled over the proper use of in-line evals. I've used them successfully in some places. But it seems that on occasion something doesn't work when I think it should.</font></div>
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<div><font size="2">First, this is a when clause that works properly using a separate eval statement. The rule activates and fires when expected:</font></div>
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<div><font size="2" face="Courier New">$rt : RuleTimer(uniqueName == "Hardware Status Request", timedOut == true)</font></div>
<div><font size="2" face="Courier New">$hw : Hardware($activelyMonitored : activelyMonitored, command == null)</font></div>
<div><font size="2" face="Courier New"> AttrBoolean(this == $activelyMonitored, currentValue == true) </font></div>
<div><font size="2" face="Courier New"> eval($hw.getStatusRequested().howOld() > $hw.getStatusPeriod())</font></div>
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<div><font size="2">However, this re-write changing to an in-line eval never fires.</font></div>
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<div><font size="2" face="Courier New">$rt : RuleTimer(uniqueName == "Hardware Status Request", timedOut == true)</font></div>
<div><font size="2" face="Courier New">$hw : Hardware($activelyMonitored : activelyMonitored, command == null, eval(statusRequested.howOld() > statusPeriod) )</font></div>
<div><font size="2" face="Courier New"> AttrBoolean(this == $activelyMonitored, currentValue == true)</font></div>
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<div><font size="2" face="Arial, sans-serif">Likewise, this re-write doesn't fire either where I sought to bind the more complex statusRequested object to a Drools variable before using it in the eval. The field statusPeriod just holds a primitive double.</font></div>
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<div><font size="2" face="Courier New">$rt : RuleTimer(uniqueName == "Hardware Status Request", timedOut == true)</font></div>
<div><font size="2" face="Courier New">$hw : Hardware($activelyMonitored : activelyMonitored, $sr : statusRequested, command == null, </font></div>
<div><font size="2" face="Courier New"> eval($sr.howOld() > statusPeriod) )</font></div>
<div><font size="2" face="Courier New"> AttrBoolean(this == $activelyMonitored, currentValue == true)</font></div>
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<div><font size="2" face="Arial, sans-serif">I haven't been able to find anything in the manual that says these other two syntaxes are wrong. Furthermore, the Drools compiler has no issues with them.</font></div>
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<div><font size="2" face="Arial, sans-serif">Thanks!</font></div>
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<div><font color="#008080" size="2" face="Tahoma, sans-serif">Allen F. Bagwell</font></div>
<div><font color="#008080" size="1" face="Tahoma, sans-serif">e-mail: <a href="mailto:afbagwe@sandia.gov" target="_blank">afbagwe@sandia.gov</a></font></div>
<div><font color="#008080" size="1" face="Tahoma, sans-serif">phone: 505/284-4517</font></div>
<div><font color="#008080" size="1" face="Tahoma, sans-serif">fax: 505/ 844-7886</font></div>
<div><font color="#008080" size="1" face="Tahoma, sans-serif"> </font></div>
<div style="margin-top: 5pt; margin-bottom: 5pt;"><font color="#008080" size="1" face="Tahoma, sans-serif">Ask your doctor if medical advice from a TV commercial is right for you.</font></div>
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<br></blockquote></div><br><br clear="all"><br>-- <br> Edson Tirelli<br> JBoss Drools Core Development<br> JBoss, a division of Red Hat @ <a href="http://www.jboss.com">www.jboss.com</a><br>