src/Tokenizer/Tokens.php
public static function clearCache($key = null)
    {
        if (null === $key) {
            self::$cache = [];

            return;
        }

        if (self::hasCache($key)) {
            unset(self::$cache[$key]);
        }
    }
public static function clearCache($key = null)
    {
        if (null === $key) {
            self::$cache = [];

            return;
        }

        if (self::hasCache($key)) {
            unset(self::$cache[$key]);
        }
    }
Clear cache - one position or all of them.

@param null|string $key position to clear, when null clear all