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<?php

    namespace Donut;


    class Helpers
    {
        /**
         * @param  string
         * @return string
         * @throws \Donut\InvalidStateException
         */
        public static function fetchUrl($url)
        {
            $s = @file_get_contents($url);

            if (is_string($s)) {
                return $s;
            }

            throw new \Donut\InvalidStateException("Download of content from URL '$url' failed.");
        }


        /**
         * @param  string|callback
         * @param  array
         * @param  object|NULL
         * @return string
         */
        public static function formatText($mask, array $placeholders, $argument = NULL)
        {
            if (is_string($mask)) {
                return strtr($mask, $placeholders);
            }

            return call_user_func($mask, $argument);
        }


        /**
         * @param  string
         * @return string
         */
        public static function stripWhitespace($s)
        {
            return trim(preg_replace('#[ \t\r\n]+#', ' ', (string) $s)); // strip whitespaces
        }
    }