src/ADT/List/Dictionary.php
public function getKeyOf( $value )
	{
		$key		= array_search( $value, $this->pairs, TRUE );
		return $key === FALSE ? NULL : $key;
	}
public function getKeyOf( $value )
	{
		$key		= array_search( $value, $this->pairs, TRUE );
		return $key === FALSE ? NULL : $key;
	}
public function getKeyOf ( $ value ) { $ key = array_search ( $ value , $ this -> pairs , TRUE ) ; return $ key === FALSE ? NULL : $ key ; }
Returns corresponding Key of a Value if Value is in Dictionary, otherwise NULL.
@access		public
@param		string		$value		Value to get Key of
@return		mixed|NULL				Key of value if found, otherwise NULL
Returns corresponding Key of a Value if Value is in Dictionary otherwise NULL .