* To hook methods, you'll need to pass an array one of two ways.
*
* Any of the syntaxes explained in the PHP documentation for the
- * {@link http://us2.php.net/manual/en/language.pseudo-types.php#language.types.callback 'callback'}
+ * {@link https://secure.php.net/manual/en/language.pseudo-types.php#language.types.callback 'callback'}
* type are valid.
*
* Also see the {@link https://codex.wordpress.org/Plugin_API Plugin API} for
*
* function example_callback( $example ) {
* // Maybe modify $example in some way.
- * return $example;
+ * return $example;
* }
* add_filter( 'example_filter', 'example_callback' );
*
- * Since WordPress 1.5.1, bound callbacks can take as many arguments as are
- * passed as parameters in the corresponding apply_filters() call. The `$accepted_args`
- * parameter allows for calling functions only when the number of args match.
+ * Bound callbacks can accept from none to the total number of arguments passed as parameters
+ * in the corresponding apply_filters() call.
*
- * *Note:* the function will return true whether or not the callback is valid.
- * It is up to you to take care. This is done for optimization purposes,
- * so everything is as quick as possible.
+ * In other words, if an apply_filters() call passes four total arguments, callbacks bound to
+ * it can accept none (the same as 1) of the arguments or up to four. The important part is that
+ * the `$accepted_args` value must reflect the number of arguments the bound callback *actually*
+ * opted to accept. If no arguments were accepted by the callback that is considered to be the
+ * same as accepting 1 argument. For example:
+ *
+ * // Filter call.
+ * $value = apply_filters( 'hook', $value, $arg2, $arg3 );
+ *
+ * // Accepting zero/one arguments.
+ * function example_callback() {
+ * ...
+ * return 'some value';
+ * }
+ * add_filter( 'hook', 'example_callback' ); // Where $priority is default 10, $accepted_args is default 1.
+ *
+ * // Accepting two arguments (three possible).
+ * function example_callback( $value, $arg2 ) {
+ * ...
+ * return $maybe_modified_value;
+ * }
+ * add_filter( 'hook', 'example_callback', 10, 2 ); // Where $priority is 10, $accepted_args is 2.
+ *
+ * *Note:* The function will return true whether or not the callback is valid.
+ * It is up to you to take care. This is done for optimization purposes, so
+ * everything is as quick as possible.
*
* @since 0.71
*
* it doesn't need to run through that process.
*
* @param string $tag The name of the filter to hook the $function_to_add callback to.
- * @param callback $function_to_add The callback to be run when the filter is applied.
+ * @param callable $function_to_add The callback to be run when the filter is applied.
* @param int $priority Optional. Used to specify the order in which the functions
* associated with a particular action are executed. Default 10.
* Lower numbers correspond with earlier execution,
* and functions with the same priority are executed
* in the order in which they were added to the action.
* @param int $accepted_args Optional. The number of arguments the function accepts. Default 1.
- * @return boolean true
+ * @return true
*/
function add_filter( $tag, $function_to_add, $priority = 10, $accepted_args = 1 ) {
global $wp_filter, $merged_filters;
* @global array $wp_filter Stores all of the filters.
*
* @param string $tag The name of the filter hook.
- * @param callback|bool $function_to_check Optional. The callback to check for. Default false.
- * @return bool|int If $function_to_check is omitted, returns boolean for whether the hook has
- * anything registered. When checking a specific function, the priority of that
- * hook is returned, or false if the function is not attached. When using the
- * $function_to_check argument, this function may return a non-boolean value
- * that evaluates to false (e.g.) 0, so use the === operator for testing the
- * return value.
+ * @param callable|bool $function_to_check Optional. The callback to check for. Default false.
+ * @return false|int If $function_to_check is omitted, returns boolean for whether the hook has
+ * anything registered. When checking a specific function, the priority of that
+ * hook is returned, or false if the function is not attached. When using the
+ * $function_to_check argument, this function may return a non-boolean value
+ * that evaluates to false (e.g.) 0, so use the === operator for testing the
+ * return value.
*/
function has_filter($tag, $function_to_check = false) {
// Don't reset the internal array pointer
}
}
- if ( false === $function_to_check || false == $has )
+ if ( false === $function_to_check || false === $has )
return $has;
if ( !$idx = _wp_filter_build_unique_id($tag, $function_to_check, false) )
* @global array $merged_filters Merges the filter hooks using this function.
* @global array $wp_current_filter Stores the list of current filters with the current one last.
*
- * @param string $tag The name of the filter hook.
- * @param mixed $value The value on which the filters hooked to `$tag` are applied on.
- * @param mixed $var Additional variables passed to the functions hooked to `$tag`.
+ * @param string $tag The name of the filter hook.
+ * @param mixed $value The value on which the filters hooked to `$tag` are applied on.
+ * @param mixed $var,... Additional variables passed to the functions hooked to `$tag`.
* @return mixed The filtered value after all hooked functions are applied to it.
*/
function apply_filters( $tag, $value ) {
$args = func_get_args();
do {
- foreach( (array) current($wp_filter[$tag]) as $the_ )
+ foreach ( (array) current($wp_filter[$tag]) as $the_ )
if ( !is_null($the_['function']) ){
$args[1] = $value;
$value = call_user_func_array($the_['function'], array_slice($args, 1, (int) $the_['accepted_args']));
/**
* Execute functions hooked on a specific filter hook, specifying arguments in an array.
*
- * @see 3.0.0
+ * @since 3.0.0
*
* @see apply_filters() This function is identical, but the arguments passed to the
* functions hooked to `$tag` are supplied using an array.
reset( $wp_filter[ $tag ] );
do {
- foreach( (array) current($wp_filter[$tag]) as $the_ )
+ foreach ( (array) current($wp_filter[$tag]) as $the_ )
if ( !is_null($the_['function']) )
$args[0] = call_user_func_array($the_['function'], array_slice($args, 0, (int) $the_['accepted_args']));
*
* @since 1.2.0
*
+ * @global array $wp_filter Stores all of the filters
+ * @global array $merged_filters Merges the filter hooks using this function.
+ *
* @param string $tag The filter hook to which the function to be removed is hooked.
- * @param callback $function_to_remove The name of the function which should be removed.
+ * @param callable $function_to_remove The name of the function which should be removed.
* @param int $priority Optional. The priority of the function. Default 10.
- * @return boolean Whether the function existed before it was removed.
+ * @return bool Whether the function existed before it was removed.
*/
function remove_filter( $tag, $function_to_remove, $priority = 10 ) {
$function_to_remove = _wp_filter_build_unique_id( $tag, $function_to_remove, $priority );
*
* @since 2.7.0
*
+ * @global array $wp_filter Stores all of the filters
+ * @global array $merged_filters Merges the filter hooks using this function.
+ *
* @param string $tag The filter to remove hooks from.
* @param int|bool $priority Optional. The priority number to remove. Default false.
- * @return bool True when finished.
+ * @return true True when finished.
*/
function remove_all_filters( $tag, $priority = false ) {
global $wp_filter, $merged_filters;
}
}
- if ( isset( $merged_filters[ $tag ] ) ) {
- unset( $merged_filters[ $tag ] );
- }
+ unset( $merged_filters[ $tag ] );
return true;
}
*
* @since 2.5.0
*
+ * @global array $wp_current_filter Stores the list of current filters with the current one last
+ *
* @return string Hook name of the current filter or action.
*/
function current_filter() {
* @since 1.2.0
*
* @param string $tag The name of the action to which the $function_to_add is hooked.
- * @param callback $function_to_add The name of the function you wish to be called.
+ * @param callable $function_to_add The name of the function you wish to be called.
* @param int $priority Optional. Used to specify the order in which the functions
* associated with a particular action are executed. Default 10.
* Lower numbers correspond with earlier execution,
* and functions with the same priority are executed
* in the order in which they were added to the action.
- * @param int $accepted_args Optional. The number of arguments the function accept. Default 1.
- * @return bool Will always return true.
+ * @param int $accepted_args Optional. The number of arguments the function accepts. Default 1.
+ * @return true Will always return true.
*/
function add_action($tag, $function_to_add, $priority = 10, $accepted_args = 1) {
return add_filter($tag, $function_to_add, $priority, $accepted_args);
* possible to create new action hooks by simply calling this function,
* specifying the name of the new hook using the `$tag` parameter.
*
- * You can pass extra arguments to the hooks, much like you can with
- * {@see apply_filters()}.
+ * You can pass extra arguments to the hooks, much like you can with apply_filters().
*
* @since 1.2.0
*
- * @global array $wp_filter Stores all of the filters
- * @global array $wp_actions Increments the amount of times action was triggered.
+ * @global array $wp_filter Stores all of the filters
+ * @global array $wp_actions Increments the amount of times action was triggered.
+ * @global array $merged_filters Merges the filter hooks using this function.
+ * @global array $wp_current_filter Stores the list of current filters with the current one last
*
- * @param string $tag The name of the action to be executed.
- * @param mixed $arg Optional. Additional arguments which are passed on to the
- * functions hooked to the action. Default empty.
- * @return null Will return null if $tag does not exist in $wp_filter array.
+ * @param string $tag The name of the action to be executed.
+ * @param mixed $arg,... Optional. Additional arguments which are passed on to the
+ * functions hooked to the action. Default empty.
*/
function do_action($tag, $arg = '') {
global $wp_filter, $wp_actions, $merged_filters, $wp_current_filter;
*
* @see do_action() This function is identical, but the arguments passed to the
* functions hooked to $tag< are supplied using an array.
- * @global array $wp_filter Stores all of the filters
- * @global array $wp_actions Increments the amount of times action was triggered.
+ * @global array $wp_filter Stores all of the filters
+ * @global array $wp_actions Increments the amount of times action was triggered.
+ * @global array $merged_filters Merges the filter hooks using this function.
+ * @global array $wp_current_filter Stores the list of current filters with the current one last
*
* @param string $tag The name of the action to be executed.
* @param array $args The arguments supplied to the functions hooked to `$tag`.
- * @return null Will return null if `$tag` does not exist in `$wp_filter` array.
*/
function do_action_ref_array($tag, $args) {
global $wp_filter, $wp_actions, $merged_filters, $wp_current_filter;
reset( $wp_filter[ $tag ] );
do {
- foreach( (array) current($wp_filter[$tag]) as $the_ )
+ foreach ( (array) current($wp_filter[$tag]) as $the_ )
if ( !is_null($the_['function']) )
call_user_func_array($the_['function'], array_slice($args, 0, (int) $the_['accepted_args']));
* @see has_filter() has_action() is an alias of has_filter().
*
* @param string $tag The name of the action hook.
- * @param callback|bool $function_to_check Optional. The callback to check for. Default false.
+ * @param callable|bool $function_to_check Optional. The callback to check for. Default false.
* @return bool|int If $function_to_check is omitted, returns boolean for whether the hook has
* anything registered. When checking a specific function, the priority of that
* hook is returned, or false if the function is not attached. When using the
* @since 1.2.0
*
* @param string $tag The action hook to which the function to be removed is hooked.
- * @param callback $function_to_remove The name of the function which should be removed.
+ * @param callable $function_to_remove The name of the function which should be removed.
* @param int $priority Optional. The priority of the function. Default 10.
- * @return boolean Whether the function is removed.
+ * @return bool Whether the function is removed.
*/
function remove_action( $tag, $function_to_remove, $priority = 10 ) {
return remove_filter( $tag, $function_to_remove, $priority );
*
* @param string $tag The action to remove hooks from.
* @param int|bool $priority The priority number to remove them from. Default false.
- * @return bool True when finished.
+ * @return true True when finished.
*/
function remove_all_actions($tag, $priority = false) {
return remove_all_filters($tag, $priority);
}
+/**
+ * Fires functions attached to a deprecated filter hook.
+ *
+ * When a filter hook is deprecated, the apply_filters() call is replaced with
+ * apply_filters_deprecated(), which triggers a deprecation notice and then fires
+ * the original filter hook.
+ *
+ * @since 4.6.0
+ *
+ * @see _deprecated_hook()
+ *
+ * @param string $tag The name of the filter hook.
+ * @param array $args Array of additional function arguments to be passed to apply_filters().
+ * @param string $version The version of WordPress that deprecated the hook.
+ * @param string $replacement Optional. The hook that should have been used. Default false.
+ * @param string $message Optional. A message regarding the change. Default null.
+ */
+function apply_filters_deprecated( $tag, $args, $version, $replacement = false, $message = null ) {
+ if ( ! has_filter( $tag ) ) {
+ return $args[0];
+ }
+
+ _deprecated_hook( $tag, $version, $replacement, $message );
+
+ return apply_filters_ref_array( $tag, $args );
+}
+
+/**
+ * Fires functions attached to a deprecated action hook.
+ *
+ * When an action hook is deprecated, the do_action() call is replaced with
+ * do_action_deprecated(), which triggers a deprecation notice and then fires
+ * the original hook.
+ *
+ * @since 4.6.0
+ *
+ * @see _deprecated_hook()
+ *
+ * @param string $tag The name of the action hook.
+ * @param array $args Array of additional function arguments to be passed to do_action().
+ * @param string $version The version of WordPress that deprecated the hook.
+ * @param string $replacement Optional. The hook that should have been used.
+ * @param string $message Optional. A message regarding the change.
+ */
+function do_action_deprecated( $tag, $args, $version, $replacement = false, $message = null ) {
+ if ( ! has_action( $tag ) ) {
+ return;
+ }
+
+ _deprecated_hook( $tag, $version, $replacement, $message );
+
+ do_action_ref_array( $tag, $args );
+}
+
//
// Functions for handling plugins.
//
*
* @since 1.5.0
*
+ * @global array $wp_plugin_paths
+ *
* @param string $file The filename of plugin.
* @return string The name of a plugin.
*/
function plugin_basename( $file ) {
global $wp_plugin_paths;
+ // $wp_plugin_paths contains normalized paths.
+ $file = wp_normalize_path( $file );
+
+ arsort( $wp_plugin_paths );
foreach ( $wp_plugin_paths as $dir => $realdir ) {
if ( strpos( $file, $realdir ) === 0 ) {
$file = $dir . substr( $file, strlen( $realdir ) );
}
}
- $file = wp_normalize_path( $file );
$plugin_dir = wp_normalize_path( WP_PLUGIN_DIR );
$mu_plugin_dir = wp_normalize_path( WPMU_PLUGIN_DIR );
*
* @since 3.9.0
*
- * @see plugin_basename()
+ * @see wp_normalize_path()
+ *
+ * @global array $wp_plugin_paths
+ *
+ * @staticvar string $wp_plugin_path
+ * @staticvar string $wpmu_plugin_path
*
* @param string $file Known path to the file.
* @return bool Whether the path was able to be registered.
global $wp_plugin_paths;
// Normalize, but store as static to avoid recalculation of a constant value
- static $wp_plugin_path, $wpmu_plugin_path;
+ static $wp_plugin_path = null, $wpmu_plugin_path = null;
if ( ! isset( $wp_plugin_path ) ) {
$wp_plugin_path = wp_normalize_path( WP_PLUGIN_DIR );
$wpmu_plugin_path = wp_normalize_path( WPMU_PLUGIN_DIR );
* @since 2.0.0
*
* @param string $file The filename of the plugin including the path.
- * @param callback $function The function hooked to the 'activate_PLUGIN' action.
+ * @param callable $function The function hooked to the 'activate_PLUGIN' action.
*/
function register_activation_hook($file, $function) {
$file = plugin_basename($file);
* @since 2.0.0
*
* @param string $file The filename of the plugin including the path.
- * @param callback $function The function hooked to the 'deactivate_PLUGIN' action.
+ * @param callable $function The function hooked to the 'deactivate_PLUGIN' action.
*/
function register_deactivation_hook($file, $function) {
$file = plugin_basename($file);
* @since 2.7.0
*
* @param string $file Plugin file.
- * @param callback $callback The callback to run when the hook is called. Must be
+ * @param callable $callback The callback to run when the hook is called. Must be
* a static method or function.
*/
function register_uninstall_hook( $file, $callback ) {
if ( is_array( $callback ) && is_object( $callback[0] ) ) {
- _doing_it_wrong( __FUNCTION__, __( 'Only a static class method or function can be used in an uninstall hook.' ), '3.1' );
+ _doing_it_wrong( __FUNCTION__, __( 'Only a static class method or function can be used in an uninstall hook.' ), '3.1.0' );
return;
}
* @since 2.5.0
* @access private
*
+ * @global array $wp_filter Stores all of the filters
+ *
* @param array $args The collected parameters from the hook that was called.
*/
function _wp_call_all_hook($args) {
reset( $wp_filter['all'] );
do {
- foreach( (array) current($wp_filter['all']) as $the_ )
+ foreach ( (array) current($wp_filter['all']) as $the_ )
if ( !is_null($the_['function']) )
call_user_func_array($the_['function'], $args);
* @access private
*
* @global array $wp_filter Storage for all of the filters and actions.
+ * @staticvar int $filter_id_count
*
* @param string $tag Used in counting how many hooks were applied
- * @param callback $function Used for creating unique id
+ * @param callable $function Used for creating unique id
* @param int|bool $priority Used in counting how many hooks were applied. If === false
* and $function is an object reference, we return the unique
* id only if it already has one, false otherwise.
- * @return string|bool Unique ID for usage as array key or false if $priority === false
- * and $function is an object reference, and it does not already have
- * a unique id.
+ * @return string|false Unique ID for usage as array key or false if $priority === false
+ * and $function is an object reference, and it does not already have
+ * a unique id.
*/
function _wp_filter_build_unique_id($tag, $function, $priority) {
global $wp_filter;