In order to fix issue of montezuma, http://code.google.com/p/montezuma/issues/detail?id=3, I suppose I found a bug of cl-ppcre.

CL-USER> (cl-ppcre:scan (cl-ppcre:create-scanner "(\w+)*\@\w+") "______________________________________" :start 0) ;; Evaluation aborted.

It hangs when the number of underscore hit a critical value. I speculate that '\w' includes underscore in regular expression would account for this bug. and replace with other character of '\w' also has this problem.

CL-USER> (cl-ppcre:scan (cl-ppcre:create-scanner "(a\w+)*\@\w+") "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa" :start 0) ;; Evaluation aborted.

but if I eliminate the last \w, it is OK. CL-USER> (cl-ppcre:scan (cl-ppcre:create-scanner "(_\w+)*\@") "_______________________________________" :start 0) NIL

I also check it in perl, Maybe perl is more efficient in regular expression operation, I raise the number of underscores, but it is OK.

$str = "john._______________________________________ __________________________________";

if ($str =~ m/(_*\w+)*@\w+/) { print "ok\n"; }

Please check it and give your comment.

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