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* HTML API: WP_HTML_Stack_Event class
* Core class used by the HTML Processor as a record for stack operations.
* This class is for internal usage of the WP_HTML_Processor class.
class WP_HTML_Stack_Event {
* Refers to popping an element off of the stack of open elements.
* Refers to pushing an element onto the stack of open elements.
* References the token associated with the stack push event,
* even if this is a pop event for that element.
* Indicates which kind of stack operation this event represents.
* May be one of the class constants.
* Indicates if the stack element is a real or virtual node.
* @param WP_HTML_Token $token Token associated with stack event, always an opening token.
* @param string $operation One of self::PUSH or self::POP.
* @param string $provenance "virtual" or "real".
public function __construct( $token, $operation, $provenance ) {
$this->operation = $operation;
$this->provenance = $provenance;