From: Lars Christensen <larsch@...>
Date: 2002-05-07T23:33:50+09:00
Subject: RegExp zero-width negative lookahead


Hi,

I'm puzzled why this doesn't work the way I expect it to.

"xxoxxxoxx" =~ /(?!x)ox+o(?!x)/      #=> nil (ok)
"xx oxxxoxx" =~ /(?!x)ox+o(?!x)/     #=> nil (ok)
"xx oxxxo xx" =~ /(?!x)ox+o(?!x)/    #=> 3 (ok)
"xxoxxxo xx" =~ /(?!x)ox+o(?!x)/     #=> 2 (huh!?)

Why is the string matched in the last case?

-- 
Lars Christensen