Explode takes a parameter to stop exploding after a set number of splits

Explode has a limit parameter. Happy day at Agaric!

This code below was written offline when I was merely hoping that explode could be limited to splitting on its first parameter only the first time said parameter is seen:

<?php
function taxonomy_xml_obo_add_pair(&$line, &$term) {
  $parts = explode(': ', $line);
  if (count($parts) == 2) {
    $key = $parts[0];
    $value = $parts[1];
    if (taxonomy_xml_obo_defines_multiple($key)) {
      if (!isset($term[$key])) {
        $term[$key] = array();
      }
      $term[$key][] = $value;
    } else {
      $term[$key] = $value;
    }
// drupal_set_message('adding line: ' . $parts[0] . ': ' . $parts[1]);
  }
  elseif (count($parts) > 2) {
    drupal_set_message('too many parts we will have to implode here if there is no way to tell explode to stop at one');
    drupal_set_message('<pre>'.var_export($parts,TRUE).'</pre>');
  }
  elseif (count($parts) == 1 && $parts[0]) {
    drupal_set_message(t("Non-parsed line: %s", $parts[0]));
  }
}
?>

Here's the code happily and much more cleanly rewritten to use explode's wonderful third parameter: the number of parts that can be made. After that, the remainder is returned as the final part without wasting any more effort in processing.

<?php
function taxonomy_xml_obo_add_pair(&$line, &$term) {
  $parts = explode(': ', $line, 2);
  if (count($parts) == 2) {
    $key = $parts[0];
    $value = $parts[1];
    if (taxonomy_xml_obo_defines_multiple($key)) {
      if (!isset($term[$key])) {
        $term[$key] = array();
      }
      $term[$key][] = $value;
    } else {
      $term[$key] = $value;
    }
  }
  elseif (count($parts) == 1 && $parts[0]) {
    drupal_set_message(t("Non-parsed line: <tt>%s</tt>", $parts[0]), 'warning');
  }
}
?>

Resolution