drupal_alter

includes/common.inc, line 2767

Versions
6 – 7
drupal_alter($type, &$data)

This dispatch function hands off structured Drupal arrays to type-specific *_alter implementations. It ensures a consistent interface for all altering operations.

Parameters

$type The data type of the structured array. 'form', 'links', 'node_content', and so on are several examples.

$data The structured array to be altered.

... Any additional params will be passed on to the called hook_$type_alter functions.

▾ 18 functions call drupal_alter()

actions_list in includes/actions.inc
Discover all action functions by invoking hook_action_info().
comment_render in modules/comment/comment.module
Renders comment(s).
drupal_get_schema in includes/common.inc
Get the schema definition of a table, or the whole database schema.
drupal_mail in includes/mail.inc
Compose and optionally send an e-mail message.
drupal_prepare_form in includes/form.inc
Prepares a structured form array by adding required elements, executing any hook_form_alter functions, and optionally inserting a validation token to prevent tampering.
locale_block in modules/locale/locale.module
Implementation of hook_block(). Displays a language switcher. Translation links may be provided by other modules.
menu_link_save in includes/menu.inc
Save a menu link.
menu_router_build in includes/menu.inc
Collect, alter and store the menu definitions.
module_rebuild_cache in includes/module.inc
Rebuild the database cache of module files.
node_view in modules/node/node.module
Generate a display of the given node.
taxonomy_link in modules/taxonomy/taxonomy.module
Implementation of hook_link().
update_calculate_project_data in modules/update/update.compare.inc
Given the installed projects and the available release data retrieved from remote servers, calculate the current status.
update_get_projects in modules/update/update.compare.inc
Fetch an array of installed and enabled projects.
upload_js in modules/upload/upload.module
Menu-callback for JavaScript-based uploads.
user_build_content in modules/user/user.module
Builds a structured array representing the profile content.
_menu_link_translate in includes/menu.inc
This function is similar to _menu_translate() but does link-specific preparation such as always calling to_arg functions.
_system_theme_data in modules/system/system.module
Helper function to scan and collect theme .info data and their engines.
_theme_build_registry in includes/theme.inc
Rebuild the hook theme_registry cache.

Code

<?php
function drupal_alter($type, &$data) {
  // PHP's func_get_args() always returns copies of params, not references, so
  // drupal_alter() can only manipulate data that comes in via the required first
  // param. For the edge case functions that must pass in an arbitrary number of
  // alterable parameters (hook_form_alter() being the best example), an array of
  // those params can be placed in the __drupal_alter_by_ref key of the $data
  // array. This is somewhat ugly, but is an unavoidable consequence of a flexible
  // drupal_alter() function, and the limitations of func_get_args().
  // @todo: Remove this in Drupal 7.
  if (is_array($data) && isset($data['__drupal_alter_by_ref'])) {
    $by_ref_parameters = $data['__drupal_alter_by_ref'];
    unset($data['__drupal_alter_by_ref']);
  }

  // Hang onto a reference to the data array so that it isn't blown away later.
  // Also, merge in any parameters that need to be passed by reference.
  $args = array(&$data);
  if (isset($by_ref_parameters)) {
    $args = array_merge($args, $by_ref_parameters);
  }

  // Now, use func_get_args() to pull in any additional parameters passed into
  // the drupal_alter() call.
  $additional_args = func_get_args();
  array_shift($additional_args);
  array_shift($additional_args);
  $args = array_merge($args, $additional_args);

  foreach (module_implements($type .'_alter') as $module) {
    $function = $module .'_'. $type .'_alter';
    call_user_func_array($function, $args);
  }
}
?>
 
 

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