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-rw-r--r--library/HTMLPurifier/Zipper.php157
1 files changed, 0 insertions, 157 deletions
diff --git a/library/HTMLPurifier/Zipper.php b/library/HTMLPurifier/Zipper.php
deleted file mode 100644
index 6e21ea070..000000000
--- a/library/HTMLPurifier/Zipper.php
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@@ -1,157 +0,0 @@
-<?php
-
-/**
- * A zipper is a purely-functional data structure which contains
- * a focus that can be efficiently manipulated. It is known as
- * a "one-hole context". This mutable variant implements a zipper
- * for a list as a pair of two arrays, laid out as follows:
- *
- * Base list: 1 2 3 4 [ ] 6 7 8 9
- * Front list: 1 2 3 4
- * Back list: 9 8 7 6
- *
- * User is expected to keep track of the "current element" and properly
- * fill it back in as necessary. (ToDo: Maybe it's more user friendly
- * to implicitly track the current element?)
- *
- * Nota bene: the current class gets confused if you try to store NULLs
- * in the list.
- */
-
-class HTMLPurifier_Zipper
-{
- public $front, $back;
-
- public function __construct($front, $back) {
- $this->front = $front;
- $this->back = $back;
- }
-
- /**
- * Creates a zipper from an array, with a hole in the
- * 0-index position.
- * @param Array to zipper-ify.
- * @return Tuple of zipper and element of first position.
- */
- static public function fromArray($array) {
- $z = new self(array(), array_reverse($array));
- $t = $z->delete(); // delete the "dummy hole"
- return array($z, $t);
- }
-
- /**
- * Convert zipper back into a normal array, optionally filling in
- * the hole with a value. (Usually you should supply a $t, unless you
- * are at the end of the array.)
- */
- public function toArray($t = NULL) {
- $a = $this->front;
- if ($t !== NULL) $a[] = $t;
- for ($i = count($this->back)-1; $i >= 0; $i--) {
- $a[] = $this->back[$i];
- }
- return $a;
- }
-
- /**
- * Move hole to the next element.
- * @param $t Element to fill hole with
- * @return Original contents of new hole.
- */
- public function next($t) {
- if ($t !== NULL) array_push($this->front, $t);
- return empty($this->back) ? NULL : array_pop($this->back);
- }
-
- /**
- * Iterated hole advancement.
- * @param $t Element to fill hole with
- * @param $i How many forward to advance hole
- * @return Original contents of new hole, i away
- */
- public function advance($t, $n) {
- for ($i = 0; $i < $n; $i++) {
- $t = $this->next($t);
- }
- return $t;
- }
-
- /**
- * Move hole to the previous element
- * @param $t Element to fill hole with
- * @return Original contents of new hole.
- */
- public function prev($t) {
- if ($t !== NULL) array_push($this->back, $t);
- return empty($this->front) ? NULL : array_pop($this->front);
- }
-
- /**
- * Delete contents of current hole, shifting hole to
- * next element.
- * @return Original contents of new hole.
- */
- public function delete() {
- return empty($this->back) ? NULL : array_pop($this->back);
- }
-
- /**
- * Returns true if we are at the end of the list.
- * @return bool
- */
- public function done() {
- return empty($this->back);
- }
-
- /**
- * Insert element before hole.
- * @param Element to insert
- */
- public function insertBefore($t) {
- if ($t !== NULL) array_push($this->front, $t);
- }
-
- /**
- * Insert element after hole.
- * @param Element to insert
- */
- public function insertAfter($t) {
- if ($t !== NULL) array_push($this->back, $t);
- }
-
- /**
- * Splice in multiple elements at hole. Functional specification
- * in terms of array_splice:
- *
- * $arr1 = $arr;
- * $old1 = array_splice($arr1, $i, $delete, $replacement);
- *
- * list($z, $t) = HTMLPurifier_Zipper::fromArray($arr);
- * $t = $z->advance($t, $i);
- * list($old2, $t) = $z->splice($t, $delete, $replacement);
- * $arr2 = $z->toArray($t);
- *
- * assert($old1 === $old2);
- * assert($arr1 === $arr2);
- *
- * NB: the absolute index location after this operation is
- * *unchanged!*
- *
- * @param Current contents of hole.
- */
- public function splice($t, $delete, $replacement) {
- // delete
- $old = array();
- $r = $t;
- for ($i = $delete; $i > 0; $i--) {
- $old[] = $r;
- $r = $this->delete();
- }
- // insert
- for ($i = count($replacement)-1; $i >= 0; $i--) {
- $this->insertAfter($r);
- $r = $replacement[$i];
- }
- return array($old, $r);
- }
-}