On Sun, Jun 1, 2008 at 3:39 PM, Rob Dixon <[EMAIL PROTECTED]> wrote:
> Dr.Ruud wrote:
>> Richard Lee schreef:
>>
>>> $pattern = '.*(?:' . join('|', @ARGV) . ')';
>>
>> Safer:
>>
>> $pattern = '.*(?:' . join('|', map quotemeta, @ARGV) . ')';
>>
>> And I would do a qr() on top of that.
>
> How? And why?
snip
how:
my $pattern = '.*(?:' . join('|', map quotemeta, @ARGV) . ')';
$pattern = qr/$pattern/;
why:
To compile the regex. In the original program, the regexes use the o
modifier to promise that $pattern won't change so the optimizer can
compile the regexes once, but if you use qr// then you don't have to
make that promise and you still only compile the regex once.
--
Chas. Owens
wonkden.net
The most important skill a programmer can have is the ability to read.
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