@since: 4.7.0

Determines whether an offset value exists.

Retrieves a value at a specified offset.

Sets a value at a specified offset.

Unsets a specified offset.

Returns the current element.

Moves forward to the next element.

Returns the key of the current element.

Checks if current position is valid.

Rewinds the Iterator to the first element.

Calls the callback functions that have been added to a filter hook.

Calls the callback functions that have been added to an action hook.

Processes the functions hooked into the ‘all’ hook.

Return the current priority level of the currently running iteration of the hook.

Normalizes filters set up before WordPress has initialized to WP_Hook objects.

Hooks a function or method to a specific filter action.