PHP Error in Log File

My log contains the messages that the following two lines of code in taxonomy_access.module:

      $tids = array_keys($edit[$vid]['term']);
      foreach ($tids as $tid) {

generate the following errors, respectively:

array_keys(): The first argument should be an array in /home/jacobson/public_html/webdev/modules/taxonomy_access/taxonomy_access.module on line 273

Invalid argument supplied for foreach() in /home/jacobson/public_html/webdev/modules/taxonomy_access/taxonomy_access.module on line 274