The KeyedIterator interface

The KeyedIterator<Tk, Tv> interface ¶

(HHVM >= 2.5)

Introduction ¶

Interface for external iterators or objects that can be iterated themselves internally.

Interface synopsis ¶

KeyedIterator<Tk, Tv> extends KeyedTraversable<Tk, Tv> extends Iterator<Tv> {

/* Methods */

abstract public mixed KeyedIterator<Tv>::key ( void )

/* Inherited methods */

abstract public Tv Iterator<Tv>::current ( void )

abstract public mixed Iterator<Tv>::key ( void )

abstract public void Iterator<Tv>::next ( void )

abstract public void Iterator<Tv>::rewind ( void )

abstract public boolean Iterator<Tv>::valid ( void )

}

Examples ¶

Example #1 Basic usage

This example demonstrates how to iterate over a keyed iterator using foreach.

<?hh
class DuplicateStrIterator implements KeyedIterator<string, string> {
  protected $it = 0;

  public function current() {
    return $this->it;
  }

  public function key() {
    return chr(65 + ($this->it % 5));
  }

  public function next() {
    $this->it++;
  }

  public function rewind() {
    $this->it = 0;
  }

  public function valid() {
    return $this->it < 10;
  }
}

$it = new DuplicateStrIterator;

foreach($it as $key => $value) {
  var_dump($key, $value);
  echo "\n";
}

The above example will output something similar to:

string(1) "A"

int(0)

string(1) "B"

int(1)

string(1) "C"

int(2)

string(1) "D"

int(3)

string(1) "E"

int(4)

string(1) "A"

int(5)

string(1) "B"

int(6)

string(1) "C"

int(7)

string(1) "D"

int(8)

string(1) "E"

int(9)

Table of Contents ¶

·         KeyedIterator<Tv>::key — Return the key of the current element

      

KeyedIterator<Tv>::key

(HHVM >= 2.5)

KeyedIterator<Tv>::key — Return the key of the current element

Description ¶

abstract public mixed KeyedIterator<Tv>::key ( void )

Returns the key of the current element.

Parameters ¶

This function has no parameters.

Return Values ¶

Returns mixed on success, or NULL on failure.

Errors/Exceptions ¶

Issues E_NOTICE on failure.