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For the case when r2 has the 'not'. When 4 doesn't exist r3 is true,
when r3 fires it asserts 4, thus r3 can no longer be true, however r4
retracts the 4 and 2 still exists, thus enabling r3 to match again
which causes the recursion - basically the insertion and retracting of
4 is toggling r3 on and off. Best thing to do is always use the audit
log so you can visualise what's going on.<br>
<br>
Mark<br>
lukichev wrote:
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<div class="Section1">
<p class="MsoNormal"><font face="Arial" size="2"><span
style="font-size: 10pt; font-family: Arial;">Dear Mark,<o:p></o:p></span></font></p>
<p class="MsoNormal"><font face="Arial" size="2"><span
style="font-size: 10pt; font-family: Arial;"><o:p> </o:p></span></font></p>
<p class="MsoNormal"><font face="Arial" size="2"><span
style="font-size: 10pt; font-family: Arial;">I have a question
concerning rule execution algorithm in
JBoss 4.0.1.<o:p></o:p></span></font></p>
<p class="MsoNormal"><font face="Arial" size="2"><span
style="font-size: 10pt; font-family: Arial;"><o:p> </o:p></span></font></p>
<p class="MsoNormal"><font face="Arial" size="2"><span
style="font-size: 10pt; font-family: Arial;">There are 2 rule sets,
one runs in a circle and another one
stops. <o:p></o:p></span></font></p>
<p class="MsoNormal"><font face="Arial" size="2"><span
style="font-size: 10pt; font-family: Arial;"><o:p> </o:p></span></font></p>
<p class="MsoNormal"><font face="Arial" size="2"><span
style="font-size: 10pt; font-family: Arial;">The first one, which
stops:<o:p></o:p></span></font></p>
<p class="MsoNormal"><font face="Arial" size="2"><span
style="font-size: 10pt; font-family: Arial;"><o:p> </o:p></span></font></p>
<p class="MsoNormal" style=""><b><font color="#960000"
face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: rgb(150, 0, 0); font-weight: bold;">rule</span></font></b><font
color="black" face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: black;"> </span></font><font
color="green" face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: green;">"r1"</span></font><font
face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New";"><o:p></o:p></span></font></p>
<p class="MsoNormal" style=""><font color="black" face="Courier New"
size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: black;">
</span></font><b><font color="#960000" face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: rgb(150, 0, 0); font-weight: bold;">when</span></font></b><font
face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New";"><o:p></o:p></span></font></p>
<p class="MsoNormal" style=""><font color="black" face="Courier New"
size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: black;">
$num1:Integer(intValue == 1)</span></font><font face="Courier New"
size="2"><span style="font-size: 10pt; font-family: "Courier New";"><o:p></o:p></span></font></p>
<p class="MsoNormal" style=""><font color="black" face="Courier New"
size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: black;">
</span></font><b><font color="#960000" face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: rgb(150, 0, 0); font-weight: bold;">then</span></font></b><font
color="black" face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: black;"> </span></font><font
face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New";"><o:p></o:p></span></font></p>
<p class="MsoNormal" style=""><font color="black" face="Courier New"
size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: black;">
</span></font><b><font color="#960000" face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: rgb(150, 0, 0); font-weight: bold;">insert</span></font></b><font
color="black" face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: black;">(</span></font><b><font
color="#960000" face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: rgb(150, 0, 0); font-weight: bold;">new</span></font></b><font
color="black" face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: black;">
Integer(2));</span></font><font face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New";"><o:p></o:p></span></font></p>
<p class="MsoNormal" style=""><b><font color="#960000"
face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: rgb(150, 0, 0); font-weight: bold;">end</span></font></b><font
face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New";"><o:p></o:p></span></font></p>
<p class="MsoNormal" style=""><font face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New";"><o:p> </o:p></span></font></p>
<p class="MsoNormal" style=""><b><font color="#960000"
face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: rgb(150, 0, 0); font-weight: bold;">rule</span></font></b><font
color="black" face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: black;"> </span></font><font
color="green" face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: green;">"r2"</span></font><font
face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New";"><o:p></o:p></span></font></p>
<p class="MsoNormal" style=""><font color="black" face="Courier New"
size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: black;">
</span></font><b><font color="#960000" face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: rgb(150, 0, 0); font-weight: bold;">when</span></font></b><font
face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New";"><o:p></o:p></span></font></p>
<p class="MsoNormal" style=""><font color="black" face="Courier New"
size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: black;">
$num1:Integer(intValue == 2)</span></font><font face="Courier New"
size="2"><span style="font-size: 10pt; font-family: "Courier New";"><o:p></o:p></span></font></p>
<p class="MsoNormal" style=""><font color="black" face="Courier New"
size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: black;">
</span></font><b><font color="#960000" face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: rgb(150, 0, 0); font-weight: bold;">then</span></font></b><font
color="black" face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: black;"> </span></font><font
face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New";"><o:p></o:p></span></font></p>
<p class="MsoNormal" style=""><font color="black" face="Courier New"
size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: black;">
</span></font><b><font color="#960000" face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: rgb(150, 0, 0); font-weight: bold;">insert</span></font></b><font
color="black" face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: black;">(</span></font><b><font
color="#960000" face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: rgb(150, 0, 0); font-weight: bold;">new</span></font></b><font
color="black" face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: black;">
Integer(3));</span></font><font face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New";"><o:p></o:p></span></font></p>
<p class="MsoNormal" style=""><b><font color="#960000"
face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: rgb(150, 0, 0); font-weight: bold;">end</span></font></b><font
face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New";"><o:p></o:p></span></font></p>
<p class="MsoNormal" style=""><font face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New";"><o:p> </o:p></span></font></p>
<p class="MsoNormal" style=""><b><font color="#960000"
face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: rgb(150, 0, 0); font-weight: bold;">rule</span></font></b><font
color="black" face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: black;"> </span></font><font
color="green" face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: green;">"r3"</span></font><font
face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New";"><o:p></o:p></span></font></p>
<p class="MsoNormal" style=""><font color="black" face="Courier New"
size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: black;">
</span></font><b><font color="#960000" face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: rgb(150, 0, 0); font-weight: bold;">when</span></font></b><font
face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New";"><o:p></o:p></span></font></p>
<p class="MsoNormal" style=""><font color="black" face="Courier New"
size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: black;">
$num1:Integer(intValue == 2)</span></font><font face="Courier New"
size="2"><span style="font-size: 10pt; font-family: "Courier New";"><o:p></o:p></span></font></p>
<p class="MsoNormal" style=""><font color="black" face="Courier New"
size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: black;">
</span></font><b><font color="#960000" face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: rgb(150, 0, 0); font-weight: bold;">then</span></font></b><font
color="black" face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: black;"> </span></font><font
face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New";"><o:p></o:p></span></font></p>
<p class="MsoNormal" style=""><font color="black" face="Courier New"
size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: black;">
</span></font><b><font color="#960000" face="Courier New"
size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: rgb(150, 0, 0); font-weight: bold;">insert</span></font></b><font
color="black" face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: black;">(</span></font><b><font
color="#960000" face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: rgb(150, 0, 0); font-weight: bold;">new</span></font></b><font
color="black" face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: black;">
Integer(4));</span></font><font face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New";"><o:p></o:p></span></font></p>
<p class="MsoNormal" style=""><b><font color="#960000"
face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: rgb(150, 0, 0); font-weight: bold;">end</span></font></b><font
face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New";"><o:p></o:p></span></font></p>
<p class="MsoNormal" style=""><font face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New";"><o:p> </o:p></span></font></p>
<p class="MsoNormal" style=""><b><font color="#960000"
face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: rgb(150, 0, 0); font-weight: bold;">rule</span></font></b><font
color="black" face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: black;"> </span></font><font
color="green" face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: green;">"r4"</span></font><font
face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New";"><o:p></o:p></span></font></p>
<p class="MsoNormal" style=""><font color="black" face="Courier New"
size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: black;">
</span></font><b><font color="#960000" face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: rgb(150, 0, 0); font-weight: bold;">when</span></font></b><font
face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New";"><o:p></o:p></span></font></p>
<p class="MsoNormal" style=""><font color="black" face="Courier New"
size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: black;">
$num1:Integer(intValue == 3)</span></font><font face="Courier New"
size="2"><span style="font-size: 10pt; font-family: "Courier New";"><o:p></o:p></span></font></p>
<p class="MsoNormal" style=""><font color="black" face="Courier New"
size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: black;">
$num2:Integer(intValue == 4)</span></font><font face="Courier New"
size="2"><span style="font-size: 10pt; font-family: "Courier New";"><o:p></o:p></span></font></p>
<p class="MsoNormal" style=""><font color="black" face="Courier New"
size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: black;">
</span></font><b><font color="#960000" face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: rgb(150, 0, 0); font-weight: bold;">then</span></font></b><font
color="black" face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: black;"> </span></font><font
face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New";"><o:p></o:p></span></font></p>
<p class="MsoNormal" style=""><font color="black" face="Courier New"
size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: black;">
</span></font><b><font color="#960000" face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: rgb(150, 0, 0); font-weight: bold;">retract</span></font></b><font
color="black" face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: black;">($num2);</span></font><font
face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New";"><o:p></o:p></span></font></p>
<p class="MsoNormal"><b><font color="#960000" face="Courier New"
size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: rgb(150, 0, 0); font-weight: bold;">end<o:p></o:p></span></font></b></p>
<p class="MsoNormal"><b><font color="#960000" face="Courier New"
size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: rgb(150, 0, 0); font-weight: bold;"><o:p> </o:p></span></font></b></p>
<p class="MsoNormal"><font face="Arial" size="2"><span
style="font-size: 10pt; font-family: Arial;">The second one, which
runs in a circle, is different from
the one above by the additional condition in r3:<o:p></o:p></span></font></p>
<p class="MsoNormal"><font face="Arial" size="2"><span
style="font-size: 10pt; font-family: Arial;"><o:p> </o:p></span></font></p>
<p class="MsoNormal" style=""><font color="black" face="Courier New"
size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: black;">
</span></font><b><font color="#960000" face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: rgb(150, 0, 0); font-weight: bold;">not</span></font></b><font
color="black" face="Courier New" size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: black;">
$num2:Integer(intValue == 4)<o:p></o:p></span></font></p>
<p class="MsoNormal" style=""><font color="black" face="Courier New"
size="2"><span
style="font-size: 10pt; font-family: "Courier New"; color: black;"><o:p> </o:p></span></font></p>
<p class="MsoNormal" style=""><font face="Arial" size="2"><span
style="font-size: 10pt; font-family: Arial;">I would expect the same
behavior of
these two rule sets, but it is different. Could you, please, comment,
why this
is so?<o:p></o:p></span></font></p>
<p class="MsoNormal" style=""><font face="Arial" size="2"><span
style="font-size: 10pt; font-family: Arial;"><o:p> </o:p></span></font></p>
<p class="MsoNormal" style=""><font face="Arial" size="2"><span
style="font-size: 10pt; font-family: Arial;">Sincerely,<o:p></o:p></span></font></p>
<p class="MsoNormal" style=""><font face="Arial" size="2"><span
style="font-size: 10pt; font-family: Arial;">Sergey Lukichev<o:p></o:p></span></font></p>
<p class="MsoNormal" style=""><font face="Arial" size="2"><span
style="font-size: 10pt; font-family: Arial;">Research Assistant,
REWERSE I1, rule
modeling and markup<o:p></o:p></span></font></p>
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</blockquote>
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