[Mpls-pm] Interesting RegEx Problem

[Andy Lester]

On Mon, Sep 19, 2005 at 09:56:53PM +0100, Ian Malpass (ian at indecorous.com) wrote:
> Oh yes, I'd forgotten about study(). Note that the documentaton is 
> equivocal about the performance benefits of study()[0], since there is 
> overhead in studying a string, and no guarantee of it giving you anything 
> in return.

As I understand it, study says "I'm going to find the first instance of each of
the 256 possible characters in the string, so that strings anchored with
a literal can start right there."

This means, if you have

    $str = "Minneapolis Perl Mongers";

then

    $str =~ /Perl/

can start right at position 12 rather than scanning to find it, and 

    $str =~ /fried cheese/

doesn't have to match anything because there's no "f" in $str,

    $str =~ /.+flooble/

doesn't do anything differently.

xox,o
Andy

-- 
Andy Lester => andy at petdance.com => www.petdance.com => AIM:petdance