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<DIV><FONT face="Courier New" size=2>I had a look into redex.</FONT></DIV>
<DIV><FONT face="Courier New" size=2></FONT> </DIV>
<DIV><FONT face="Courier New" size=2>IT'S GREAT!</FONT></DIV>
<DIV><FONT face="Courier New" size=2></FONT> </DIV>
<DIV><FONT face="Courier New" size=2>I carefully copy-pasted the example
from</FONT></DIV>
<DIV><FONT face="Courier New" size=2><A
href="http://redex.plt-scheme.org/lam-v.html">http://redex.plt-scheme.org/lam-v.html</A></FONT></DIV>
<DIV><FONT face="Courier New" size=2></FONT> </DIV>
<DIV><FONT face="Courier New" size=2>I don't yet understand how it avoids
looping on</FONT></DIV>
<DIV><FONT face="Courier New" size=2>(traces red (term ((λ (x) (x x)) (λ (x) (x
x)))))</FONT></DIV>
<DIV><FONT face="Courier New" size=2>but I'll study on that. </FONT></DIV>
<DIV><FONT face="Courier New" size=2></FONT> </DIV>
<DIV><FONT face="Courier New" size=2>However, when I try:</FONT></DIV>
<DIV><FONT face="Courier New" size=2></FONT> </DIV>
<DIV><FONT face="Courier New" size=2>(traces red (term ((λ (x) (x x x)) (λ (x)
(x x x)))))</FONT></DIV>
<DIV><FONT face="Courier New" size=2></FONT> </DIV>
<DIV><FONT face="Courier New" size=2>I get:</FONT></DIV>
<DIV><FONT face="Courier New" size=2></FONT> </DIV>
<DIV><FONT face="Courier New" size=2>Welcome to DrScheme, version
4.1.4.1-svn17jan2009 [3m].<BR>Language: Module; memory limit: 1000
megabytes.<BR>syntax: incompatible ellipsis match counts for template in:
...</FONT></DIV>
<DIV><FONT face="Courier New" size=2>No indication where.</FONT></DIV>
<DIV><FONT face="Courier New" size=2></FONT> </DIV>
<DIV><FONT face="Courier New" size=2>I carefully checked all ellipses,
</FONT><FONT face="Courier New" size=2>but cannot find any improper
use.</FONT></DIV>
<DIV><FONT face="Courier New" size=2></FONT> </DIV>
<DIV><FONT face="Courier New" size=2>I also noticed that</FONT></DIV>
<DIV><FONT face="Courier New" size=2>(traces red (term (((λ x (λ y x)) y)
z)))</FONT></DIV>
<DIV><FONT face="Courier New" size=2>does not contract.</FONT></DIV>
<DIV><FONT face="Courier New" size=2>That's due to the capture
avoidance.</FONT></DIV>
<DIV><FONT face="Courier New" size=2>I'll try to add alpha conversion for this
case.</FONT></DIV>
<DIV><FONT face="Courier New" size=2>Jos</FONT></DIV></BODY></HTML>