Fatal error: Unsupported operand types in .... includes/common.inc on line 1265

I looked through the code, and found this:

/**
 * Generate a URL from a Drupal menu path. Will also pass-through existing URLs.
 *
 * @param $path
 *   The Drupal path being linked to, such as "admin/content/node", or an
 *   existing URL like "http://drupal.org/".  The special path
 *   '<front>' may also be given and will generate the site's base URL.
 * @param $options
 *   An associative array of additional options, with the following keys:
 *   - 'query'
 *       A query string to append to the link, or an array of query key/value
 *       properties.
 *   - 'fragment'
 *       A fragment identifier (or named anchor) to append to the link.
 *       Do not include the '#' character.
 *   - 'absolute' (default FALSE)
 *       Whether to force the output to be an absolute link (beginning with
 *       http:). Useful for links that will be displayed outside the site, such
 *       as in an RSS feed.
 *   - 'alias' (default FALSE)
 *       Whether the given path is an alias already.
 *   - 'external'
 *       Whether the given path is an external URL.
 *   - 'language'
 *       An optional language object. Used to build the URL to link to and
 *       look up the proper alias for the link.
 *   - 'base_url'
 *       Only used internally, to modify the base URL when a language dependent
 *       URL requires so.
 *   - 'prefix'
 *       Only used internally, to modify the path when a language dependent URL
 *       requires so.
 * @return
 *   A string containing a URL to the given path.
 *
 * When creating links in modules, consider whether l() could be a better
 * alternative than url().
 */
function url($path = NULL, $options = array()) {
  // Merge in defaults.
  $options += array(
    'fragment' => '',
    'query' => '',
    'absolute' => FALSE,
    'alias' => FALSE,
    'prefix' => ''
  );
  if (!isset($options['external'])) {
    // Return an external link if $path contains an allowed absolute URL.
    // Only call the slow filter_xss_bad_protocol if $path contains a ':' before
    // any / ? or #.
    $colonpos = strpos($path, ':');
    $options['external'] = ($colonpos !== FALSE && !preg_match('![/?#]!', substr($path, 0, $colonpos)) && filter_xss_bad_protocol($path, FALSE) == check_plain($path));
  }

Line 1265 is the ); right under 'prefix' => '' in the array. So, I'm guessing it's a problem with the url generation when it takes you back to the main thread? I've been reading other threads about "unsupported operand types" and most of them have to do with syntax errors, but I see nothing.