format_string placeholder allowing html

Allow formatted html placeholder, without check_plain, in format_string. My suggestion is ~:

bootstrap.inc

function format_string($string, array $args = array()) {
  // Transform arguments before inserting them.
  foreach ($args as $key => $value) {
    switch ($key[0]) {
      case '@':
        // Escaped only.
        $args[$key] = check_plain($value);
        break;

      case '~':
        // Html.
        $args[$key] = html_entity_decode($value);
        break;

      case '%':
      default:
        // Escaped and placeholder.
        $args[$key] = drupal_placeholder($value);
        break;

      case '!':
        // Pass-through.
    }
  }
  return strtr($string, $args);
}

When inserting watchdog messages, sometimes it is useful to print formatted html variables. In my case, when debugging an error and in some special cases, I like to print stack trace:

/**
 * Pone un mensaje en el watchdog.
 * ATENCIÓN: usar de la siguiente forma:
 * <pre>
 * if (variable_get('my_module_debug', false)) {
 *   debugMsg(
 * }</pre>
 *
 * o
 * <pre>
 * if (variable_get('my_module_debug_exhaustivo', false)) {
 *   debugMsg(
 * }</pre>
 *
 * @param string $type Clasificación del mensaje
 * @param string $message Texto del mensaje con parámetros
 * @param array $variables Parámetros del texto
 * @param string $file normalmente __FILE__
 * @param string $function normalmente __FUNCTION__
 * @param string $line normalmente __LINE__
 * @param boolean $printTrace Indica si volcar la pila
 * @param int $severity por defecto WATHCDOB_DEBUG. Disponibles:
 *   - WATCHDOG_EMERGENCY: Emergency, system is unusable.
 *   - WATCHDOG_ALERT: Alert, action must be taken immediately.
 *   - WATCHDOG_CRITICAL: Critical conditions.
 *   - WATCHDOG_ERROR: Error conditions.
 *   - WATCHDOG_WARNING: Warning conditions.
 *   - WATCHDOG_NOTICE: (default) Normal but significant conditions.
 *   - WATCHDOG_INFO: Informational messages.
 *   - WATCHDOG_DEBUG: Debug-level messages.
 */
function debugMsg($type, $message, $variables, $file = null, $function = null, $line = null, $printTrace = false, $severity = WATCHDOG_DEBUG) {
  if ($file != null && $function != null && $line != null) {
    $message .= "<p>File: @file<br/>Function: @function()<br/>Line: @@@line</p>";

    if (!is_array($variables) || empty($variables)) {
      $variables = array();
    }
    $variables = array_merge($variables, array('@file' => $file, '@function' => $function, '@line' => $line, ));
  }

  if ($printTrace) {
    $message .= "<p>##Stack Trace:<br/>";
    $message .= "###########################################<br/>";
    $message .= '@trace';
    $message .= "<br/>###########################################<br/>";
    $message .= "###End Stack Trace</p>";

    $trace = implode('<br/>-------------------------------------------<br/>', get_debug_print_backtrace());
    if (!is_array($variables) || empty($variables)) {
      $variables = array();
    }
    $variables = array_merge($variables, array('@trace' => check_plain($trace), )); // print_r(get_debug_print_backtrace(), TRUE), ));
  }

  watchdog($type, $message, $variables, $severity);
}

function debugMsgErr($type, $message, $variables, $e, $file = null, $function = null, $line = null, $printTrace = true) {
  $message .= "<p>Error: @error</p>";
  $newvars = array_merge($variables, array('@error' => $e->getMessage(), ));
  debugMsg($type, $message, $newvars, $file, $function, $line, $printTrace, WATCHDOG_ERROR);
}

function get_debug_print_backtrace($traces_to_ignore = 1){
  $traces = debug_backtrace();
  $ret = array();

  foreach($traces as $i => $call){
    if ($i < $traces_to_ignore ) {
      continue;
    }

    $object = '';
    if (isset($call['class'])) {
      $object = $call['class'] . $call['type'];
      if (is_array($call['args'])) {
        foreach ($call['args'] as &$arg) {
          get_arg($arg);
        }
      }
    }

    if (is_array($call['args'])) {
      foreach ($call['args'] as &$arg) {
        get_arg($arg);
      }
    }

    $line = '#[' . str_pad($i - $traces_to_ignore, 3, '] ') . $object . $call['function'] . '<br/>';

    if (isset($call['file'])) {
      $line .= 'Fichero: ' . $call['file'] . '<br/>';
    }
    if (isset($call['file'])) {
      $line .= 'Linea: ' . $call['line'] . '<br/>';
    }

    $line .= 'Argumentos:';
    $line .= '<pre>' . print_r($call['args'], TRUE) . '</pre>';

    //$line = '<pre>' . print_r($call, TRUE) . '</pre>';
    $ret[] = $line;
  }

  return $ret;
}

function get_arg(&$arg) {
  if (is_object($arg)) {
    $arr = (array)$arg;
    $args = array();
    foreach($arr as $key => $value) {
      if (strpos($key, chr(0)) !== false) {
        $key = '';    // Private variable found
      }
      $args[] =  '<br/>    ['.$key.'] => '.get_arg($value);
    }

    $arg = get_class($arg) . ' Object ('.implode(',', $args).')';
  }
}