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</o:shapelayout></xml><![endif]--></head><body lang=DE-AT link=blue vlink=purple><div class=WordSection1><p class=MsoNormal>Hi,<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><span lang=EN-US>I want to delete a list of facts from the working memory and therefore created following rule:<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal style='text-autospace:none'><b><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:#960000'>rule</span></b><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:black'> </span><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:green'>"delete rule"</span><span lang=EN-US style='font-size:10.0pt;font-family:Consolas'><o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><b><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:#960000'> agenda-group</span></b><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:black'> </span><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:green'>"evaluation"</span><span lang=EN-US style='font-size:10.0pt;font-family:Consolas'><o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><b><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:#960000'> salience</span></b><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:black'> 50</span><span lang=EN-US style='font-size:10.0pt;font-family:Consolas'><o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><b><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:#960000'> no-loop</span></b><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:black'> </span><b><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:#960000'>true</span></b><span lang=EN-US style='font-size:10.0pt;font-family:Consolas'><o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span lang=EN-US style='font-size:10.0pt;font-family:Consolas'><o:p> </o:p></span></p><p class=MsoNormal style='text-autospace:none'><b><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:#960000'> when</span></b><span lang=EN-US style='font-size:10.0pt;font-family:Consolas'><o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:black'> $facts : ArrayList(size > 0) </span><b><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:#960000'>from</span></b><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:black'> </span><b><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:#960000'>collect</span></b><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:black'> (Fact())</span><span lang=EN-US style='font-size:10.0pt;font-family:Consolas'><o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><b><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:#960000'> then</span></b><span lang=EN-US style='font-size:10.0pt;font-family:Consolas'><o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:black'> logger.info(</span><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:green'>"delete rule, number of facts in list: "</span><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:black'> + $facts.size());</span><span lang=EN-US style='font-size:10.0pt;font-family:Consolas'><o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:black'> </span><span lang=EN-US style='font-size:10.0pt;font-family:Consolas'><o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><b><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:#960000'> for</span></b><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:black'> (</span><b><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:#960000'>int</span></b><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:black'> i = 0; i < $facts.size(); i++) {</span><span lang=EN-US style='font-size:10.0pt;font-family:Consolas'><o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:black'> Fact f = (Fact)$facts.get(i);</span><span lang=EN-US style='font-size:10.0pt;font-family:Consolas'><o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:black'> logger.info(</span><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:green'>"retract fact id: "</span><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:black'> + f.getId());</span><span lang=EN-US style='font-size:10.0pt;font-family:Consolas'><o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:black'> </span><b><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:#960000'>retract</span></b><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:black'>(f);</span><span lang=EN-US style='font-size:10.0pt;font-family:Consolas'><o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:black'> }</span><span lang=EN-US style='font-size:10.0pt;font-family:Consolas'><o:p></o:p></span></p><p class=MsoNormal><b><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:#960000'>end</span></b><span lang=EN-US><o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>When inserting 10 facts with IDs 1 to 10 and then fire all rules, I get following result:<o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:black'>delete rule, number of facts in list: 10</span><span lang=EN-US style='font-size:10.0pt;font-family:Consolas'><o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:black'>retract fact id: 1</span><span lang=EN-US style='font-size:10.0pt;font-family:Consolas'><o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:black'>retract fact id: 3</span><span lang=EN-US style='font-size:10.0pt;font-family:Consolas'><o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:black'>retract fact id: 5</span><span lang=EN-US style='font-size:10.0pt;font-family:Consolas'><o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:black'>retract fact id: 7</span><span lang=EN-US style='font-size:10.0pt;font-family:Consolas'><o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:black'>retract fact id: 9</span><span lang=EN-US><o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>but, the facts 2, 4, 6, 8 and 10 are not deleted. I would have expected to set “no-loop” to true, as I do some modification of facts and don’t want that this rule is fired again with the same facts. When I set “no-loop” to false, I get following result:<o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:black'>delete rule, number of facts in list: 10</span><span lang=EN-US style='font-size:10.0pt;font-family:Consolas'><o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:black'>retract fact id: 1</span><span lang=EN-US style='font-size:10.0pt;font-family:Consolas'><o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:black'>retract fact id: 3</span><span lang=EN-US style='font-size:10.0pt;font-family:Consolas'><o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:black'>retract fact id: 5</span><span lang=EN-US style='font-size:10.0pt;font-family:Consolas'><o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:black'>retract fact id: 7</span><span lang=EN-US style='font-size:10.0pt;font-family:Consolas'><o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:black'>retract fact id: 9</span><span lang=EN-US style='font-size:10.0pt;font-family:Consolas'><o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:black'>delete rule, number of facts in list: 5</span><span lang=EN-US style='font-size:10.0pt;font-family:Consolas'><o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:black'>retract fact id: 2</span><span lang=EN-US style='font-size:10.0pt;font-family:Consolas'><o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:black'>retract fact id: 6</span><span lang=EN-US style='font-size:10.0pt;font-family:Consolas'><o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:black'>retract fact id: 10</span><span lang=EN-US style='font-size:10.0pt;font-family:Consolas'><o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:black'>delete rule, number of facts in list: 2</span><span lang=EN-US style='font-size:10.0pt;font-family:Consolas'><o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:black'>retract fact id: 4</span><span lang=EN-US style='font-size:10.0pt;font-family:Consolas'><o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:black'>delete rule, number of facts in list: 1</span><span lang=EN-US style='font-size:10.0pt;font-family:Consolas'><o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span lang=EN-US style='font-size:10.0pt;font-family:Consolas;color:black'>retract fact id: 8</span><span lang=EN-US style='font-size:10.0pt;font-family:Consolas'><o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>now, all facts are deleted but the “delete rule” was fired 4 times. Is this the intended behavior of Drools? Is there a way to fire a rule only once and delete a list of facts?<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>I can reproduce this behavior with Drools 5.5.0.Final and 6.0.0.Beta2 but did not try any other version.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>Best Regards,<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>Wolfgang<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p></div></body></html>