<?php
$date_day_pattern = '(?:0[1-9]|[12][0-9]|3[01])';
$date_month_pattern = '(?:0[1-9]|1[0-2])';
$date_year_pattern = '(?:[12][0-9]|20[12][0-9])';
$input = "dksj dkk\n49.. dk /ak 01-05-2012 hey\nkdks";
$prefix_pattern = '^(.*?)\s*';//(?<=[^\n]*)';
$date_pattern = "(?<!\d|\d )($date_day_pattern)[^\d\n]?($date_month_pattern)[^\d\n]?($date_year_pattern)(?!\d)";
echo "$date_pattern\n";
preg_match("/$prefix_pattern$date_pattern/m", $input, $matches);
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