tag in the page)
    preg_match('~
([^<]+)
~', $html, $matches);
    $constantList = $matches[1];

    /**
     * Parse the cURL constant lines. Possible formats:
     *
     * Name                            Introduced    Deprecated  Removed
     * CURLOPT_CRLFILE                 7.19.0
     * CURLOPT_DNS_USE_GLOBAL_CACHE    7.9.3         7.11.1
     * CURLOPT_FTPASCII                7.1           7.11.1      7.15.5
     * CURLOPT_HTTPREQUEST             7.1           -           7.15.5
     */
    $regexp = '/^([A-Za-z0-9_]+) +([0-9\.]+)(?: +([0-9\.\-]+))?(?: +([0-9\.]+))?/m';
    preg_match_all($regexp, $constantList, $matches, PREG_SET_ORDER);

    $constants = [];

    foreach ($matches as $match) {
        $name       = $match[1];
        $introduced = $match[2];
        $deprecated = $match[3] ?? null;
        $removed    = $match[4] ?? null;

        if (in_array($name, IGNORED_CONSTANTS, true) || !preg_match(CONSTANTS_REGEX_PATTERN, $name)) {
            // not a wanted constant
            continue;
        }

        if ($deprecated === '-') { // deprecated version can be a hyphen
            $deprecated = null;
        }

        $constants[$name] = [$introduced, $deprecated, $removed];
    }

    return $constants;
}

/**
 * Parses the defined cURL constants from the PHP extension source code.
 *
 * The result is a numeric array whose values are the constant names.
 *
 * @return array
 */
function getSourceConstants() : array
{
    $source = file_get_contents(SOURCE_FILE);

    preg_match_all('/REGISTER_CURL_CONSTANT\(([A-Za-z0-9_]+)\)/', $source, $matches);

    $constants = [];

    foreach ($matches[1] as $name) {
        if ($name === '__c') { // macro
            continue;
        }

        if (!preg_match(CONSTANTS_REGEX_PATTERN, $name)) {
            // not a wanted constant
            continue;
        }

        $constants[] = $name;
    }

    return $constants;
}

/**
 * Converts a version number to its hex representation as used in the extension source code.
 *
 * Example: 7.25.1 => 0x071901
 *
 * @param string $version
 *
 * @return string
 *
 * @throws \RuntimeException
 */
function getHexVersion(string $version) : string
{
    $parts = explode('.', $version);

    if (count($parts) === 2) {
        $parts[] = '0';
    }

    if (count($parts) !== 3) {
        throw new \RuntimeException('Invalid version number: ' . $version);
    }

    $hex = '0x';

    foreach ($parts as $value) {
        if (! ctype_digit($value) || strlen($value) > 3) {
            throw new \RuntimeException('Invalid version number: ' . $version);
        }

        $value = (int) $value;

        if ($value > 255) {
            throw new \RuntimeException('Invalid version number: ' . $version);
        }

        $value = dechex($value);

        if (strlen($value) === 1) {
            $value = '0' . $value;
        }

        $hex .= $value;
    }

    return $hex;
}

/**
 * A simple helper to create ASCII tables.
 * It assumes that the same number of columns is always given to add().
 */
class AsciiTable
{
    /**
     * @var array
     */
    private $values = [];

    /**
     * @var array
     */
    private $length = [];

    /**
     * @var int
     */
    private $padding = 4;

    /**
     * @param string[] $values
     *
     * @return void
     */
    public function add(string ...$values) : void
    {
        $this->values[] = $values;

        foreach ($values as $key => $value) {
            $length = strlen($value);

            if (isset($this->length[$key])) {
                $this->length[$key] = max($this->length[$key], $length);
            } else {
                $this->length[$key] = $length;
            }
        }
    }

    /**
     * @return string
     */
    public function __toString() : string
    {
        $result = '';

        foreach ($this->values as $values) {
            foreach ($values as $key => $value) {
                if ($key !== 0) {
                    $result .= str_repeat(' ', $this->padding);
                }

                $result .= str_pad($value, $this->length[$key]);
            }

            $result .= "\n";
        }

        return $result;
    }
}