/home/joan/000www/repo/spirit/1.0/core/extensions/filter/base_filters/date_filter.php

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<?php
class DateFilter implements FilterInterface
{
    public static function execute ($s, $options)
    {
        $patron = '/(19|20)(\d{2})-(\d{1,2})-(\d{1,2})/';
        if (preg_match($patron, $s, $regs)) {
            return $regs[0];
        } else {
            return "";
        }
    }
}

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