Compiling regular expressions once for reuse

[alokito]

I need to search many (thousands) of strings with the same regular expression. Is it possible to compile the regular expression once and reuse it in php as you can in python and java and perl? for instance , here's a good perl example from http://www.perl.com/doc/manual/html/pod/perlop.html:

foreach $pattern (@pattern_list) {
        my $re = qr/$pattern/;
        foreach $line (@lines) {
            if($line =~ /$re/) {
                do_something($line);
            }
        }
    }

[zq29]

Like this?
[code]<?php
$strings = array("here","are","thousands","of","strings","2006-08-07","blah","blah");
foreach($strings as $s) {
    if(ereg("([0-9]{4})-([0-9]{2})-([0-9]{2})",$s)) echo "<p>$s is in a date format.</p>";
}
?>[/code]