On 11/24/09 Tue Nov 24, 2009 4:42 PM, "Orchid Fairy (兰花仙子)" <practicalp...@gmail.com> scribbled:
> On Wed, Nov 25, 2009 at 8:38 AM, Shawn H Corey <shawnhco...@gmail.com> wrote: > >> >> It seems to be picking up an extra empty string after a non-zero length >> match. >> > > Thanks John and Shawn. > Yup what let me be confused is that, why there is an additional empty > string there? You get 4 matches because there are four places in the string 'aXXXb' that can be matched by 'X*'. Note that a "place" in this case is a position between characters. The places are: 1. before the a 2. after the a 3. before the b 4. after the b You could actually say that there are two additional places in the string that can be matched by 'X*': after the first and second X's. However, because the '*' modifier is "greedy", once it matches the first X, it gobbles up the rest of the X's, so the next match attempt is started after the last X. As a result, you get 4 matches total for the 'g' modifier, which always starts a match test at the position following the previous match. -- To unsubscribe, e-mail: beginners-unsubscr...@perl.org For additional commands, e-mail: beginners-h...@perl.org http://learn.perl.org/
