#76802: Introduce placeholder magic into t()

See: http://drupal.org/node/64279#t-placeholders

9 files changed, 111 insertions, 66 deletions

diff --git a/includes/common.inc b/includes/common.inc
index c84d358a8..3cd1a3feb 100644
--- a/includes/common.inc
+++ b/includes/common.inc
@@ -277,7 +277,7 @@ function drupal_site_offline() {
   drupal_set_header('HTTP/1.0 503 Service unavailable');
   drupal_set_title(t('Site off-line'));
   print theme('maintenance_page', filter_xss_admin(variable_get('site_offline_message',
-    t('%site is currently under maintenance. We should be back shortly. Thank you for your patience.', array('%site' => variable_get('site_name', t('This Drupal site')))))));
+    t('@site is currently under maintenance. We should be back shortly. Thank you for your patience.', array('@site' => variable_get('site_name', t('This Drupal site')))))));
 }
 
 /**
@@ -285,7 +285,7 @@ function drupal_site_offline() {
  */
 function drupal_not_found() {
   drupal_set_header('HTTP/1.0 404 Not Found');
-  watchdog('page not found', t('%page not found.', array('%page' => theme('placeholder', $_GET['q']))), WATCHDOG_WARNING);
+  watchdog('page not found', t('%page not found.', array('%page' => $_GET['q'])), WATCHDOG_WARNING);
 
   // Keep old path for reference
   if (!isset($_REQUEST['destination'])) {
@@ -313,7 +313,7 @@ function drupal_not_found() {
  */
 function drupal_access_denied() {
   drupal_set_header('HTTP/1.0 403 Forbidden');
-  watchdog('access denied', t('%page denied access.', array('%page' => theme('placeholder', $_GET['q']))), WATCHDOG_WARNING, l(t('view'), $_GET['q']));
+  watchdog('access denied', t('%page denied access.', array('%page' => $_GET['q'])), WATCHDOG_WARNING, l(t('view'), $_GET['q']));
 
   // Keep old path for reference
   if (!isset($_REQUEST['destination'])) {
@@ -567,8 +567,8 @@ function locale_initialize() {
  * is acceptable, if necessary. The suggested syntax for a link embedded
  * within a translation string is:
  * @code
- *   $msg = t('You must log in below or <a href="%url">create a new
- *             account</a> before viewing the next page.', array('%url'
+ *   $msg = t('You must log in below or <a href="@url">create a new
+ *             account</a> before viewing the next page.', array('@url'
  *             => url('user/register')));
  * @endcode
  * We suggest the same syntax for links to other sites. This makes it easy to
@@ -580,6 +580,11 @@ function locale_initialize() {
  * @param $args
  *   An associative array of replacements to make after translation. Incidences
  *   of any key in this array are replaced with the corresponding value.
+ *   Based on the first character of the key, the value is escaped and/or themed:
+ *    - !variable: inserted as is
+ *    - @variable: escape plain text to HTML (check_plain)
+ *    - %variable: escape text and theme as a placeholder for user-submitted
+ *      content (check_plain + theme_placeholder)
  * @return
  *   The translated string.
  */
@@ -588,16 +593,35 @@ function t($string, $args = 0) {
   if (function_exists('locale') && $locale != 'en') {
     $string = locale($string);
   }
-
   if (!$args) {
     return $string;
   }
   else {
+    // Transform arguments before inserting them
+    array_walk($args, '_t');
     return strtr($string, $args);
   }
 }
 
 /**
+ * Helper function: apply the appropriate transformation to st() and t()
+ * placeholders.
+ */
+function _t(&$value, $key) {
+  switch ($key[0]) {
+    // Escaped only
+    case '@':
+      $value = check_plain($value);
+      return;
+    // Escaped and placeholder
+    case '%':
+    default:
+      $value = theme('placeholder', $value);
+      return;
+  }
+}
+
+/**
  * @defgroup validation Input validation
  * @{
  * Functions to validate user input.
@@ -778,27 +802,27 @@ function format_xml_elements($array) {
  *   singular, to ease translation (e.g. use "1 new comment" instead of "1 new").
  * @param $plural
  *   The string for the plural case. Please make sure it is clear this is plural,
- *   to ease translation. Use %count in place of the item count, as in "%count
+ *   to ease translation. Use @count in place of the item count, as in "@count
  *   new comments".
  * @return
  *   A translated string.
  */
 function format_plural($count, $singular, $plural) {
-  if ($count == 1) return t($singular, array("%count" => $count));
+  if ($count == 1) return t($singular, array("@count" => $count));
 
   // get the plural index through the gettext formula
   $index = (function_exists('locale_get_plural')) ? locale_get_plural($count) : -1;
   if ($index < 0) { // backward compatibility
-    return t($plural, array("%count" => $count));
+    return t($plural, array("@count" => $count));
   }
   else {
     switch ($index) {
       case "0":
-        return t($singular, array("%count" => $count));
+        return t($singular, array("@count" => $count));
       case "1":
-        return t($plural, array("%count" => $count));
+        return t($plural, array("@count" => $count));
       default:
-        return t(strtr($plural, array("%count" => '%count['. $index .']')), array('%count['. $index .']' => $count));
+        return t(strtr($plural, array("@count" => '@count['. $index .']')), array('@count['. $index .']' => $count));
     }
   }
 }
@@ -821,7 +845,7 @@ function format_size($size) {
     $size = round($size / 1024, 2);
     $suffix = t('MB');
   }
-  return t('%size %suffix', array('%size' => $size, '%suffix' => $suffix));
+  return t('@size @suffix', array('@size' => $size, '@suffix' => $suffix));
 }
 
 /**
@@ -835,7 +859,7 @@ function format_size($size) {
  *   A translated string representation of the interval.
  */
 function format_interval($timestamp, $granularity = 2) {
-  $units = array('1 year|%count years' => 31536000, '1 week|%count weeks' => 604800, '1 day|%count days' => 86400, '1 hour|%count hours' => 3600, '1 min|%count min' => 60, '1 sec|%count sec' => 1);
+  $units = array('1 year|@count years' => 31536000, '1 week|@count weeks' => 604800, '1 day|@count days' => 86400, '1 hour|@count hours' => 3600, '1 min|@count min' => 60, '1 sec|@count sec' => 1);
   $output = '';
   foreach ($units as $key => $value) {
     $key = explode('|', $key);
diff --git a/includes/database.pgsql.inc b/includes/database.pgsql.inc
index 7f03bceaa..c1e6d5d6e 100644
--- a/includes/database.pgsql.inc
+++ b/includes/database.pgsql.inc
@@ -365,7 +365,7 @@ function db_table_exists($table) {
 function db_check_setup() {
   $encoding = db_result(db_query('SHOW server_encoding'));
   if (!in_array(strtolower($encoding), array('unicode', 'utf8'))) {
-    drupal_set_message(t('Your PostgreSQL database is set up with the wrong character encoding (%encoding). It is possible it will not work as expected. It is advised to recreate it with UTF-8/Unicode encoding. More information can be found in the <a href="%url">PostgreSQL documentation</a>.', array('%encoding' => $encoding, '%url' => 'http://www.postgresql.org/docs/7.4/interactive/multibyte.html')), 'status');
+    drupal_set_message(t('Your PostgreSQL database is set up with the wrong character encoding (%encoding). It is possible it will not work as expected. It is advised to recreate it with UTF-8/Unicode encoding. More information can be found in the <a href="@url">PostgreSQL documentation</a>.', array('%encoding' => $encoding, '@url' => 'http://www.postgresql.org/docs/7.4/interactive/multibyte.html')), 'status');
   }
 }
 
diff --git a/includes/file.inc b/includes/file.inc
index fd1e09c78..6ab1d77f8 100644
--- a/includes/file.inc
+++ b/includes/file.inc
@@ -89,12 +89,12 @@ function file_check_directory(&$directory, $mode = 0, $form_item = NULL) {
   // Check if directory exists.
   if (!is_dir($directory)) {
     if (($mode & FILE_CREATE_DIRECTORY) && @mkdir($directory)) {
-      drupal_set_message(t('The directory %directory has been created.', array('%directory' => theme('placeholder', $directory))));
+      drupal_set_message(t('The directory %directory has been created.', array('%directory' => $directory)));
       @chmod($directory, 0775); // Necessary for non-webserver users.
     }
     else {
       if ($form_item) {
-        form_set_error($form_item, t('The directory %directory does not exist.', array('%directory' => theme('placeholder', $directory))));
+        form_set_error($form_item, t('The directory %directory does not exist.', array('%directory' => $directory)));
       }
       return FALSE;
     }
@@ -103,11 +103,11 @@ function file_check_directory(&$directory, $mode = 0, $form_item = NULL) {
   // Check to see if the directory is writable.
   if (!is_writable($directory)) {
     if (($mode & FILE_MODIFY_PERMISSIONS) && @chmod($directory, 0775)) {
-      drupal_set_message(t('The permissions of directory %directory have been changed to make it writable.', array('%directory' => theme('placeholder', $directory))));
+      drupal_set_message(t('The permissions of directory %directory have been changed to make it writable.', array('%directory' => $directory)));
     }
     else {
-      form_set_error($form_item, t('The directory %directory is not writable', array('%directory' => theme('placeholder', $directory))));
-      watchdog('file system', t('The directory %directory is not writable, because it does not have the correct permissions set.', array('%directory' => theme('placeholder', $directory))), WATCHDOG_ERROR);
+      form_set_error($form_item, t('The directory %directory is not writable', array('%directory' => $directory)));
+      watchdog('file system', t('The directory %directory is not writable, because it does not have the correct permissions set.', array('%directory' => $directory)), WATCHDOG_ERROR);
       return FALSE;
     }
   }
@@ -118,7 +118,7 @@ function file_check_directory(&$directory, $mode = 0, $form_item = NULL) {
       fclose($fp);
     }
     else {
-      $message = t("Security warning: Couldn't write .htaccess file. Please create a .htaccess file in your %directory directory which contains the following lines: <code>%htaccess</code>", array('%directory' => theme('placeholder', $directory), '%htaccess' => '<br />'. str_replace("\n", '<br />', check_plain($htaccess_lines))));
+      $message = t("Security warning: Couldn't write .htaccess file. Please create a .htaccess file in your %directory directory which contains the following lines: <code>!htaccess</code>", array('%directory' => $directory, '!htaccess' => '<br />'. nl2br(check_plain($htaccess_lines))));
       form_set_error($form_item, $message);
       watchdog('security', $message, WATCHDOG_ERROR);
     }
@@ -204,17 +204,17 @@ function file_check_upload($source = 'upload') {
 
       case UPLOAD_ERR_INI_SIZE:
       case UPLOAD_ERR_FORM_SIZE:
-        drupal_set_message(t('The file %file could not be saved, because it exceeds the maximum allowed size for uploads.', array('%file' => theme('placeholder', $source))), 'error');
+        drupal_set_message(t('The file %file could not be saved, because it exceeds the maximum allowed size for uploads.', array('%file' => $source)), 'error');
         return 0;
 
       case UPLOAD_ERR_PARTIAL:
       case UPLOAD_ERR_NO_FILE:
-        drupal_set_message(t('The file %file could not be saved, because the upload did not complete.', array('%file' => theme('placeholder', $source))), 'error');
+        drupal_set_message(t('The file %file could not be saved, because the upload did not complete.', array('%file' => $source)), 'error');
         return 0;
 
       // Unknown error
       default:
-        drupal_set_message(t('The file %file could not be saved. An unknown error has occurred.', array('%file' => theme('placeholder', $source))),'error');
+        drupal_set_message(t('The file %file could not be saved. An unknown error has occurred.', array('%file' => $source)),'error');
         return 0;
     }
 
@@ -238,7 +238,7 @@ function file_check_upload($source = 'upload') {
     // This overcomes open_basedir restrictions for future file operations.
     if (!move_uploaded_file($_FILES["edit"]["tmp_name"][$source], $file->filepath)) {
       drupal_set_message(t('File upload error. Could not move uploaded file.'));
-      watchdog('file', t('Upload Error. Could not move uploaded file(%file) to destination(%destination).', array('%file' => theme('placeholder', $_FILES["edit"]["tmp_name"][$source]), '%destination' => theme('placeholder', $file->filepath))));
+      watchdog('file', t('Upload Error. Could not move uploaded file (%file) to destination (%destination).', array('%file' => $_FILES["edit"]["tmp_name"][$source], '%destination' => $file->filepath)));
       return FALSE;
     }
 
@@ -318,8 +318,8 @@ function file_copy(&$source, $dest = 0, $replace = FILE_EXISTS_RENAME) {
   // Make sure we at least have a valid directory.
   if ($basename === FALSE) {
     $source = is_object($source) ? $source->filepath : $source;
-    drupal_set_message(t('The selected file %file could not be uploaded, because the destination %directory is not properly configured.', array('%file' => theme('placeholder', $source), '%directory' => theme('placeholder', $dest))), 'error');
-    watchdog('file system', t('The selected file %file could not not be uploaded, because the destination %directory could not be found, or because its permissions do not allow the file to be written.', array('%file' => theme('placeholder', $source), '%directory' => theme('placeholder', $dest))), WATCHDOG_ERROR);
+    drupal_set_message(t('The selected file %file could not be uploaded, because the destination %directory is not properly configured.', array('%file' => $source, '%directory' => $dest)), 'error');
+    watchdog('file system', t('The selected file %file could not not be uploaded, because the destination %directory could not be found, or because its permissions do not allow the file to be written.', array('%file' => $source, '%directory' => $dest)), WATCHDOG_ERROR);
     return 0;
   }
 
@@ -334,7 +334,7 @@ function file_copy(&$source, $dest = 0, $replace = FILE_EXISTS_RENAME) {
 
   $source = realpath($source);
   if (!file_exists($source)) {
-    drupal_set_message(t('The selected file %file could not be copied, because no file by that name exists. Please check that you supplied the correct filename.', array('%file' => theme('placeholder', $source))), 'error');
+    drupal_set_message(t('The selected file %file could not be copied, because no file by that name exists. Please check that you supplied the correct filename.', array('%file' => $source)), 'error');
     return 0;
   }
 
@@ -366,13 +366,13 @@ function file_copy(&$source, $dest = 0, $replace = FILE_EXISTS_RENAME) {
           break;
 
         case FILE_EXISTS_ERROR:
-          drupal_set_message(t('The selected file %file could not be copied, because a file by that name already exists in the destination.', array('%file' => theme('placeholder', $source))), 'error');
+          drupal_set_message(t('The selected file %file could not be copied, because a file by that name already exists in the destination.', array('%file' => $source)), 'error');
           return 0;
       }
     }
 
     if (!@copy($source, $dest)) {
-      drupal_set_message(t('The selected file %file could not be copied.', array('%file' => theme('placeholder', $source))), 'error');
+      drupal_set_message(t('The selected file %file could not be copied.', array('%file' => $source)), 'error');
       return 0;
     }
 
@@ -421,7 +421,7 @@ function file_move(&$source, $dest = 0, $replace = FILE_EXISTS_RENAME) {
     if ($path_original == $path_current || file_delete($path_original)) {
       return 1;
     }
-    drupal_set_message(t('The removal of the original file %file has failed.', array('%file' => theme('placeholder', $path_original))), 'error');
+    drupal_set_message(t('The removal of the original file %file has failed.', array('%file' => $path_original)), 'error');
   }
   return 0;
 }
diff --git a/includes/form.inc b/includes/form.inc
index 3fe498406..291933d1f 100644
--- a/includes/form.inc
+++ b/includes/form.inc
@@ -283,7 +283,7 @@ function _form_validate($elements, $form_id = NULL) {
       // and a textfield could return '0' and empty('0') returns TRUE so we
       // need a special check for the '0' string.
       if ($elements['#required'] && empty($elements['#value']) && $elements['#value'] !== '0') {
-        form_error($elements, t('%name field is required.', array('%name' => $elements['#title'])));
+        form_error($elements, t('!name field is required.', array('!name' => $elements['#title'])));
       }
 
       // Add legal choice check if element has #options. Can be skipped, but then you must validate your own element.
@@ -299,7 +299,7 @@ function _form_validate($elements, $form_id = NULL) {
           foreach ($value as $v) {
             if (!isset($options[$v])) {
               form_error($elements, t('An illegal choice has been detected. Please contact the site administrator.'));
-              watchdog('form', t('Illegal choice %choice in %name element.', array('%choice' => theme('placeholder', check_plain($v)), '%name' => theme_placeholder(empty($elements['#title']) ? $elements['#parents'][0] : $elements['#title']))), WATCHDOG_ERROR);
+              watchdog('form', t('Illegal choice %choice in !name element.', array('%choice' => $v, '!name' => empty($elements['#title']) ? $elements['#parents'][0] : $elements['#title'])), WATCHDOG_ERROR);
             }
           }
         }
@@ -1147,10 +1147,10 @@ function theme_form_element($element, $value) {
   if (!empty($element['#title'])) {
     $title = $element['#title'];
     if (!empty($element['#id'])) {
-      $output .= ' <label for="'. form_clean_id($element['#id']) .'">'. t('%title: %required', array('%title' => $title, '%required' => $required)) ."</label>\n";
+      $output .= ' <label for="'. form_clean_id($element['#id']) .'">'. t('!title: !required', array('!title' => $title, '!required' => $required)) ."</label>\n";
     }
     else {
-      $output .= ' <label>'. t('%title: %required', array('%title' => $title, '%required' => $required)) ."</label>\n";
+      $output .= ' <label>'. t('!title: !required', array('!title' => $title, '!required' => $required)) ."</label>\n";
     }
   }
 
diff --git a/includes/image.inc b/includes/image.inc
index f14afa9c0..37f377c1a 100644
--- a/includes/image.inc
+++ b/includes/image.inc
@@ -58,7 +58,7 @@ function image_toolkit_invoke($method, $params = array()) {
       return call_user_func_array($function, $params);
     }
     else {
-      watchdog('php', t("The selected image handling toolkit '%toolkit' can not correctly process '%function'.", array('%toolkit' => "<em>$toolkit</em>", '%function' => "<em>$function</em>")), WATCHDOG_ERROR);
+      watchdog('php', t("The selected image handling toolkit %toolkit can not correctly process %function.", array('%toolkit' => $toolkit, '%function' => $function)), WATCHDOG_ERROR);
       return FALSE;
     }
   }
@@ -184,7 +184,7 @@ function image_gd_settings() {
     return t('The built-in GD2 toolkit is installed and working properly.');
   }
   else {
-    form_set_error('image_toolkit', t("The built-in GD image toolkit requires that the GD module for PHP be installed and configured properly. For more information see %url.", array('%url' => '<a href="http://php.net/image">http://php.net/image</a>')));
+    form_set_error('image_toolkit', t('The built-in GD image toolkit requires that the GD module for PHP be installed and configured properly. For more information see <a href="@url">PHP\'s image documentation</a>.', array('@url' => 'http://php.net/image')));
     return FALSE;
   }
 }
diff --git a/includes/install.inc b/includes/install.inc
index 77dd88d54..1de8261ee 100644
--- a/includes/install.inc
+++ b/includes/install.inc
@@ -550,5 +550,27 @@ function install_goto($path) {
  */
 function st($string, $args = array()) {
   require_once './includes/theme.inc';
-  return strtr($string, array_map('theme_placeholder', $args));
+  $GLOBALS['theme'] = 'theme';
+  // Transform arguments before inserting them
+  array_walk($args, '_st');
+  return strtr($string, $args);
+}
+
+/**
+ * Helper function: apply the appropriate transformation to st() and t() placeholders.
+ */ 
+function _st(&$value, $key) {
+  switch ($key[0]) {
+    // Escaped only
+    case '@':
+      $value = check_plain($value);
+      return;
+    // Escaped and placeholder
+    case '%':
+    default:
+      $value = '<em>'. check_plain($value) .'</em>';
+      return;
+    // Pass-through
+    case '!':
+  }
 }
diff --git a/includes/locale.inc b/includes/locale.inc
index 2128ac76f..0f6e3ee1d 100644
--- a/includes/locale.inc
+++ b/includes/locale.inc
@@ -23,13 +23,13 @@ function _locale_add_language($code, $name, $onlylanguage = TRUE) {
   // the language addition, we need to inform the user on how to start
   // a translation
   if ($onlylanguage) {
-    drupal_set_message(t('The language %locale has been created, and can now be used to import a translation. More information is available in the <a href="%locale-help">help screen</a>.', array('%locale' => theme('placeholder', t($name)), '%locale-help' => url('admin/help/locale'))));
+    drupal_set_message(t('The language %locale has been created and can now be used to import a translation. More information is available in the <a href="@locale-help">help screen</a>.', array('%locale' => t($name), '@locale-help' => url('admin/help/locale'))));
   }
   else {
-    drupal_set_message(t('The language %locale has been created.', array('%locale' => theme('placeholder', t($name)))));
+    drupal_set_message(t('The language %locale has been created.', array('%locale' => t($name))));
   }
 
-  watchdog('locale', t('The %language language (%locale) has been created.', array('%language' => theme('placeholder', $name), '%locale' => theme('placeholder', $code))));
+  watchdog('locale', t('The %language language (%locale) has been created.', array('%language' => $name, '%locale' => $code)));
 }
 
 /**
@@ -154,7 +154,7 @@ function _locale_admin_manage_add_screen() {
     '#size' => 12,
     '#maxlength' => 60,
     '#required' => TRUE,
-    '#description' => t("Commonly this is an <a href=\"%iso-codes\">ISO 639 language code</a> with an optional country code for regional variants. Examples include 'en', 'en-US' and 'zh-cn'.", array('%iso-codes' => 'http://www.w3.org/WAI/ER/IG/ert/iso639.htm')),
+    '#description' => t("Commonly this is an <a href=\"@iso-codes\">ISO 639 language code</a> with an optional country code for regional variants. Examples include 'en', 'en-US' and 'zh-cn'.", array('@iso-codes' => 'http://www.w3.org/WAI/ER/IG/ert/iso639.htm')),
   );
   $form['custom language']['langname'] = array('#type' => 'textfield',
     '#title' => t('Language name in English'),
@@ -175,7 +175,7 @@ function _locale_admin_manage_add_screen() {
  */
 function locale_add_language_form_validate($form_id, $form_values) {
   if ($duplicate = db_num_rows(db_query("SELECT locale FROM {locales_meta} WHERE locale = '%s'", $form_values['langcode'])) != 0) {
-    form_set_error(t('The language %language (%code) already exists.', array('%language' => theme('placeholder', check_plain($form_values['langname'])), '%code' => theme('placeholder', $form_values['langcode']))));
+    form_set_error(t('The language %language (%code) already exists.', array('%language' => $form_values['langname'], '%code' => $form_values['langcode'])));
   }
 
   if (!isset($form_values['langname'])) {
@@ -259,7 +259,7 @@ function _locale_admin_import_submit($form_id, $form_values) {
   // Now import strings into the language
   $file = file_check_upload('file');
   if ($ret = _locale_import_po($file, $form_values['langcode'], $form_values['mode']) == FALSE) {
-    $message = t('The translation import of %filename failed.', array('%filename' => theme('placeholder', $file->filename)));
+    $message = t('The translation import of %filename failed.', array('%filename' => $file->filename));
     drupal_set_message($message, 'error');
     watchdog('locale', $message, WATCHDOG_ERROR);
   }
@@ -469,7 +469,7 @@ function _locale_import_po($file, $lang, $mode) {
   list($headerdone, $additions, $updates) = _locale_import_one_string('report', $mode);
 
   if (!$headerdone) {
-    drupal_set_message(t('The translation file %filename appears to have a missing or malformed header.', array('%filename' => theme('placeholder', $file->filename))), 'error');
+    drupal_set_message(t('The translation file %filename appears to have a missing or malformed header.', array('%filename' => $file->filename)), 'error');
   }
 
   // rebuild locale cache
@@ -479,7 +479,7 @@ function _locale_import_po($file, $lang, $mode) {
   menu_rebuild();
 
   drupal_set_message(t('The translation was successfully imported. There are %number newly created translated strings and %update strings were updated.', array('%number' => $additions, '%update' => $updates)));
-  watchdog('locale', t('Imported %file into %locale: %number new strings added and %update updated.', array('%file' => theme('placeholder', $file->filename), '%locale' => theme('placeholder', $lang), '%number' => $additions, '%update' => $updates)));
+  watchdog('locale', t('Imported %file into %locale: %number new strings added and %update updated.', array('%file' => $file->filename, '%locale' => $lang, '%number' => $additions, '%update' => $updates)));
   return TRUE;
 }
 
@@ -982,8 +982,8 @@ function _locale_import_append_plural($entry, $key) {
   }
 
   // First remove any possibly false indices, then add new ones
-  $entry = preg_replace('/(%count)\[[0-9]\]/', '\\1', $entry);
-  return preg_replace('/(%count)/', "\\1[$key]", $entry);
+  $entry = preg_replace('/(@count)\[[0-9]\]/', '\\1', $entry);
+  return preg_replace('/(@count)/', "\\1[$key]", $entry);
 }
 
 /**
@@ -1083,7 +1083,7 @@ function _locale_export_po($language) {
       $header .= "\"Plural-Forms: nplurals=". $meta->plurals ."; plural=". strtr($meta->formula, '$', '') .";\\n\"\n";
     }
     $header .= "\n";
-    watchdog('locale', t('Exported %locale translation file: %filename.', array('%locale' => theme('placeholder', $meta->name), '%filename' => theme('placeholder', $filename))));
+    watchdog('locale', t('Exported %locale translation file: %filename.', array('%locale' => $meta->name, '%filename' => $filename)));
   }
 
   // Generating Portable Object Template
@@ -1104,7 +1104,7 @@ function _locale_export_po($language) {
     $header .= "\"Content-Transfer-Encoding: 8bit\\n\"\n";
     $header .= "\"Plural-Forms: nplurals=INTEGER; plural=EXPRESSION;\\n\"\n";
     $header .= "\n";
-    watchdog('locale', t('Exported translation file: %filename.', array('%filename' => theme('placeholder', $filename))));
+    watchdog('locale', t('Exported translation file: %filename.', array('%filename' => $filename)));
   }
 
   // Start download process
@@ -1212,7 +1212,7 @@ function _locale_export_wrap($str, $len) {
  * Removes plural index information from a string
  */
 function _locale_export_remove_plural($entry) {
-  return preg_replace('/(%count)\[[0-9]\]/', '\\1', $entry);
+  return preg_replace('/(@count)\[[0-9]\]/', '\\1', $entry);
 }
 
 /**
diff --git a/includes/theme.inc b/includes/theme.inc
index 265653a27..e9bd3f3f6 100644
--- a/includes/theme.inc
+++ b/includes/theme.inc
@@ -338,9 +338,8 @@ function theme_get_setting($setting_name, $refresh = FALSE) {
  */
 
 /**
- * Format a dynamic text string for emphasized display in a placeholder.
- *
- * E.g. t('Added term %term', array('%term' => theme('placeholder', $term)))
+ * Formats text for emphasized display in a placeholder inside a sentence.
+ * Used automatically by t().
  *
  * @param $text
  *   The text to format (plain-text).
@@ -606,10 +605,10 @@ function theme_node($node, $teaser = FALSE, $page = FALSE) {
   }
 
   if ($page == 0) {
-    $output .= t('%title by %name', array('%title' => '<h2 class="title">'. check_plain($node->title) .'</h2>', '%name' => theme('username', $node)));
+    $output .= t('!title by !name', array('!title' => '<h2 class="title">'. check_plain($node->title) .'</h2>', '!name' => theme('username', $node)));
   }
   else {
-    $output .= t('by %name', array('%name' => theme('username', $node)));
+    $output .= t('by !name', array('!name' => theme('username', $node)));
   }
 
   if (count($terms)) {
@@ -889,7 +888,7 @@ function theme_item_list($items = array(), $title = NULL, $type = 'ul', $attribu
  * Returns code that emits the 'more help'-link.
  */
 function theme_more_help_link($url) {
-  return '<div class="more-help-link">' . t('[<a href="%link">more help...</a>]', array('%link' => check_url($url))) . '</div>';
+  return '<div class="more-help-link">' . t('[<a href="@link">more help...</a>]', array('@link' => check_url($url))) . '</div>';
 }
 
 /**
diff --git a/includes/unicode.inc b/includes/unicode.inc
index 26b9c212e..81fe2ffeb 100644
--- a/includes/unicode.inc
+++ b/includes/unicode.inc
@@ -31,7 +31,7 @@ function _unicode_check($errors = FALSE) {
   // Note: we check if U+E2 is in the range U+E0 - U+E1. This test returns TRUE on old PCRE versions.
   if (preg_match('/[à-á]/u', 'â')) {
     if ($errors) {
-      form_set_error('unicode', t('The PCRE library in your PHP installation is outdated. This will cause problems when handling Unicode text. If you are running PHP 4.3.3 or higher, make sure you are using the PCRE library supplied by PHP. Please refer to the <a href="%url">PHP PCRE documentation</a> for more information.', array('%url' => 'http://www.php.net/pcre')));
+      form_set_error('unicode', t('The PCRE library in your PHP installation is outdated. This will cause problems when handling Unicode text. If you are running PHP 4.3.3 or higher, make sure you are using the PCRE library supplied by PHP. Please refer to the <a href="@url">PHP PCRE documentation</a> for more information.', array('@url' => 'http://www.php.net/pcre')));
     }
     return UNICODE_ERROR;
   }
@@ -44,25 +44,25 @@ function _unicode_check($errors = FALSE) {
   // Check mbstring configuration
   if (ini_get('mbstring.func_overload') != 0) {
     if ($errors) {
-      form_set_error('unicode', t('Multibyte string function overloading in PHP is active and must be disabled. Check the php.ini <em>mbstring.func_overload</em> setting. Please refer to the <a href="%url">PHP mbstring documentation</a> for more information.', array('%url' => 'http://www.php.net/mbstring')));
+      form_set_error('unicode', t('Multibyte string function overloading in PHP is active and must be disabled. Check the php.ini <em>mbstring.func_overload</em> setting. Please refer to the <a href="@url">PHP mbstring documentation</a> for more information.', array('@url' => 'http://www.php.net/mbstring')));
     }
     return UNICODE_ERROR;
   }
   if (ini_get('mbstring.encoding_translation') != 0) {
     if ($errors) {
-      form_set_error('unicode', t('Multibyte string input conversion in PHP is active and must be disabled. Check the php.ini <em>mbstring.encoding_translation</em> setting. Please refer to the <a href="%url">PHP mbstring documentation</a> for more information.', array('%url' => 'http://www.php.net/mbstring')));
+      form_set_error('unicode', t('Multibyte string input conversion in PHP is active and must be disabled. Check the php.ini <em>mbstring.encoding_translation</em> setting. Please refer to the <a href="@url">PHP mbstring documentation</a> for more information.', array('@url' => 'http://www.php.net/mbstring')));
     }
     return UNICODE_ERROR;
   }
   if (ini_get('mbstring.http_input') != 'pass') {
     if ($errors) {
-      form_set_error('unicode', t('Multibyte string input conversion in PHP is active and must be disabled. Check the php.ini <em>mbstring.http_input</em> setting. Please refer to the <a href="%url">PHP mbstring documentation</a> for more information.', array('%url' => 'http://www.php.net/mbstring')));
+      form_set_error('unicode', t('Multibyte string input conversion in PHP is active and must be disabled. Check the php.ini <em>mbstring.http_input</em> setting. Please refer to the <a href="@url">PHP mbstring documentation</a> for more information.', array('@url' => 'http://www.php.net/mbstring')));
     }
     return UNICODE_ERROR;
   }
   if (ini_get('mbstring.http_output') != 'pass') {
     if ($errors) {
-      form_set_error('unicode', t('Multibyte string output conversion in PHP is active and must be disabled. Check the php.ini <em>mbstring.http_output</em> setting. Please refer to the <a href="%url">PHP mbstring documentation</a> for more information.', array('%url' => 'http://www.php.net/mbstring')));
+      form_set_error('unicode', t('Multibyte string output conversion in PHP is active and must be disabled. Check the php.ini <em>mbstring.http_output</em> setting. Please refer to the <a href="@url">PHP mbstring documentation</a> for more information.', array('@url' => 'http://www.php.net/mbstring')));
     }
     return UNICODE_ERROR;
   }
@@ -78,8 +78,8 @@ function _unicode_check($errors = FALSE) {
  */
 function unicode_settings() {
   $status = _unicode_check(TRUE);
-  $options = array(UNICODE_SINGLEBYTE => t('Standard PHP: operations on Unicode strings are emulated on a best-effort basis. Install the <a href="%url">PHP mbstring extension</a> for improved Unicode support.', array('%url' => 'http://www.php.net/mbstring')),
-                   UNICODE_MULTIBYTE => t('Multi-byte: operations on Unicode strings are supported through the <a href="%url">PHP mbstring extension</a>.', array('%url' => 'http://www.php.net/mbstring')),
+  $options = array(UNICODE_SINGLEBYTE => t('Standard PHP: operations on Unicode strings are emulated on a best-effort basis. Install the <a href="@url">PHP mbstring extension</a> for improved Unicode support.', array('@url' => 'http://www.php.net/mbstring')),
+                   UNICODE_MULTIBYTE => t('Multi-byte: operations on Unicode strings are supported through the <a href="@url">PHP mbstring extension</a>.', array('@url' => 'http://www.php.net/mbstring')),
                    UNICODE_ERROR => t('Invalid: the current configuration is incompatible with Drupal.'));
   $form['settings'] = array('#type' => 'item', '#title' => t('String handling method'), '#value' => $options[$status]);
   return $form;
@@ -128,7 +128,7 @@ function drupal_xml_parser_create(&$data) {
       $data = ereg_replace('^(<\?xml[^>]+encoding)="([^"]+)"', '\\1="utf-8"', $out);
     }
     else {
-      watchdog('php', t("Could not convert XML encoding '%s' to UTF-8.", array('%s' => $encoding)), WATCHDOG_WARNING);
+      watchdog('php', t("Could not convert XML encoding %s to UTF-8.", array('%s' => $encoding)), WATCHDOG_WARNING);
       return 0;
     }
   }
@@ -161,7 +161,7 @@ function drupal_convert_to_utf8($data, $encoding) {
     $out = @recode_string($encoding .'..utf-8', $data);
   }
   else {
-    watchdog('php', t("Unsupported encoding '%s'. Please install iconv, GNU recode or mbstring for PHP.", array('%s' => $encoding)), WATCHDOG_ERROR);
+    watchdog('php', t("Unsupported encoding %s. Please install iconv, GNU recode or mbstring for PHP.", array('%s' => $encoding)), WATCHDOG_ERROR);
     return FALSE;
   }