interface Collection

PersistentObject.php in drupal/core/vendor/doctrine/common/lib/Doctrine/Common/Persistence/PersistentObject.php

interface Collection extends Countable, IteratorAggregate, ArrayAccess {

  /**
   * Adds an element at the end of the collection.
   *
   * @param mixed $element The element to add.
   * @return boolean Always TRUE.
   */
  function add($element);

  /**
   * Clears the collection, removing all elements.
   */
  function clear();

  /**
   * Checks whether an element is contained in the collection.
   * This is an O(n) operation, where n is the size of the collection.
   *
   * @param mixed $element The element to search for.
   * @return boolean TRUE if the collection contains the element, FALSE otherwise.
   */
  function contains($element);

  /**
   * Checks whether the collection is empty (contains no elements).
   *
   * @return boolean TRUE if the collection is empty, FALSE otherwise.
   */
  function isEmpty();

  /**
   * Removes the element at the specified index from the collection.
   *
   * @param string|integer $key The kex/index of the element to remove.
   * @return mixed The removed element or NULL, if the collection did not contain the element.
   */
  function remove($key);

  /**
   * Removes the specified element from the collection, if it is found.
   *
   * @param mixed $element The element to remove.
   * @return boolean TRUE if this collection contained the specified element, FALSE otherwise.
   */
  function removeElement($element);

  /**
   * Checks whether the collection contains an element with the specified key/index.
   *
   * @param string|integer $key The key/index to check for.
   * @return boolean TRUE if the collection contains an element with the specified key/index,
   *          FALSE otherwise.
   */
  function containsKey($key);

  /**
   * Gets the element at the specified key/index.
   *
   * @param string|integer $key The key/index of the element to retrieve.
   * @return mixed
   */
  function get($key);

  /**
   * Gets all keys/indices of the collection.
   *
   * @return array The keys/indices of the collection, in the order of the corresponding
   *          elements in the collection.
   */
  function getKeys();

  /**
   * Gets all values of the collection.
   *
   * @return array The values of all elements in the collection, in the order they
   *          appear in the collection.
   */
  function getValues();

  /**
   * Sets an element in the collection at the specified key/index.
   *
   * @param string|integer $key The key/index of the element to set.
   * @param mixed $value The element to set.
   */
  function set($key, $value);

  /**
   * Gets a native PHP array representation of the collection.
   *
   * @return array
   */
  function toArray();

  /**
   * Sets the internal iterator to the first element in the collection and
   * returns this element.
   *
   * @return mixed
   */
  function first();

  /**
   * Sets the internal iterator to the last element in the collection and
   * returns this element.
   *
   * @return mixed
   */
  function last();

  /**
   * Gets the key/index of the element at the current iterator position.
   *
   */
  function key();

  /**
   * Gets the element of the collection at the current iterator position.
   *
   */
  function current();

  /**
   * Moves the internal iterator position to the next element.
   *
   */
  function next();

  /**
   * Tests for the existence of an element that satisfies the given predicate.
   *
   * @param Closure $p The predicate.
   * @return boolean TRUE if the predicate is TRUE for at least one element, FALSE otherwise.
   */
  function exists(Closure $p);

  /**
   * Returns all the elements of this collection that satisfy the predicate p.
   * The order of the elements is preserved.
   *
   * @param Closure $p The predicate used for filtering.
   * @return Collection A collection with the results of the filter operation.
   */
  function filter(Closure $p);

  /**
   * Applies the given predicate p to all elements of this collection,
   * returning true, if the predicate yields true for all elements.
   *
   * @param Closure $p The predicate.
   * @return boolean TRUE, if the predicate yields TRUE for all elements, FALSE otherwise.
   */
  function forAll(Closure $p);

  /**
   * Applies the given function to each element in the collection and returns
   * a new collection with the elements returned by the function.
   *
   * @param Closure $func
   * @return Collection
   */
  function map(Closure $func);

  /**
   * Partitions this collection in two collections according to a predicate.
   * Keys are preserved in the resulting collections.
   *
   * @param Closure $p The predicate on which to partition.
   * @return array An array with two elements. The first element contains the collection
   *               of elements where the predicate returned TRUE, the second element
   *               contains the collection of elements where the predicate returned FALSE.
   */
  function partition(Closure $p);

  /**
   * Gets the index/key of a given element. The comparison of two elements is strict,
   * that means not only the value but also the type must match.
   * For objects this means reference equality.
   *
   * @param mixed $element The element to search for.
   * @return mixed The key/index of the element or FALSE if the element was not found.
   */
  function indexOf($element);

  /**
   * Extract a slice of $length elements starting at position $offset from the Collection.
   *
   * If $length is null it returns all elements from $offset to the end of the Collection.
   * Keys have to be preserved by this method. Calling this method will only return the
   * selected slice and NOT change the elements contained in the collection slice is called on.
   *
   * @param int $offset
   * @param int $length
   * @return array
   */
  function slice($offset, $length = null);

}