<?
print_r(array_chunk(get_declared_classes(),10));
?>

<?
print_r(array_chunk(get_declared_classes(),10,true));
?>

Array
(
    [0] => Array
        (
            [0] => stdClass
            [1] => Exception
            [2] => ErrorException
            [3] => COMPersistHelper
            [4] => com_exception
            [5] => com_safearray_proxy
            [6] => variant
            [7] => com
            [8] => dotnet
            [9] => ReflectionException
        )

    [1] => Array
        (
            [0] => Reflection
            [1] => ReflectionFunctionAbstract
            [2] => ReflectionFunction
            [3] => ReflectionParameter
            [4] => ReflectionMethod
            [5] => ReflectionClass
            [6] => ReflectionObject
            [7] => ReflectionProperty
            [8] => ReflectionExtension
            [9] => DateTime
        )

    [2] => Array
        (
            [0] => DateTimeZone
            [1] => LibXMLError
            [2] => __PHP_Incomplete_Class
            [3] => php_user_filter
            [4] => Directory
            [5] => SimpleXMLElement
            [6] => DOMException
            [7] => DOMStringList
            [8] => DOMNameList
            [9] => DOMImplementationList
        )

    [3] => Array
        (
            [0] => DOMImplementationSource
            [1] => DOMImplementation
            [2] => DOMNode
            [3] => DOMNameSpaceNode
            [4] => DOMDocumentFragment
            [5] => DOMDocument
            [6] => DOMNodeList
            [7] => DOMNamedNodeMap
            [8] => DOMCharacterData
            [9] => DOMAttr
        )

    [4] => Array
        (
            [0] => DOMElement
            [1] => DOMText
            [2] => DOMComment
            [3] => DOMTypeinfo
            [4] => DOMUserDataHandler
            [5] => DOMDomError
            [6] => DOMErrorHandler
            [7] => DOMLocator
            [8] => DOMConfiguration
            [9] => DOMCdataSection
        )

    [5] => Array
        (
            [0] => DOMDocumentType
            [1] => DOMNotation
            [2] => DOMEntity
            [3] => DOMEntityReference
            [4] => DOMProcessingInstruction
            [5] => DOMStringExtend
            [6] => DOMXPath
            [7] => RecursiveIteratorIterator
            [8] => IteratorIterator
            [9] => FilterIterator
        )

    [6] => Array
        (
            [0] => RecursiveFilterIterator
            [1] => ParentIterator
            [2] => LimitIterator
            [3] => CachingIterator
            [4] => RecursiveCachingIterator
            [5] => NoRewindIterator
            [6] => AppendIterator
            [7] => InfiniteIterator
            [8] => RegexIterator
            [9] => RecursiveRegexIterator
        )

    [7] => Array
        (
            [0] => EmptyIterator
            [1] => ArrayObject
            [2] => ArrayIterator
            [3] => RecursiveArrayIterator
            [4] => SplFileInfo
            [5] => DirectoryIterator
            [6] => RecursiveDirectoryIterator
            [7] => SplFileObject
            [8] => SplTempFileObject
            [9] => SimpleXMLIterator
        )

    [8] => Array
        (
            [0] => LogicException
            [1] => BadFunctionCallException
            [2] => BadMethodCallException
            [3] => DomainException
            [4] => InvalidArgumentException
            [5] => LengthException
            [6] => OutOfRangeException
            [7] => RuntimeException
            [8] => OutOfBoundsException
            [9] => OverflowException
        )

    [9] => Array
        (
            [0] => RangeException
            [1] => UnderflowException
            [2] => UnexpectedValueException
            [3] => SplObjectStorage
            [4] => XMLReader
            [5] => XMLWriter
            [6] => mysqli_sql_exception
            [7] => mysqli_driver
            [8] => mysqli
            [9] => mysqli_warning
        )

    [10] => Array
        (
            [0] => mysqli_result
            [1] => mysqli_stmt
            [2] => PDOException
            [3] => PDO
            [4] => PDOStatement
            [5] => PDORow
            [6] => SoapClient
            [7] => SoapVar
            [8] => SoapServer
            [9] => SoapFault
        )

    [11] => Array
        (
            [0] => SoapParam
            [1] => SoapHeader
            [2] => SQLiteDatabase
            [3] => SQLiteResult
            [4] => SQLiteUnbuffered
            [5] => SQLiteException
        )

)