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    10 <!DOCTYPE concept

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    12 <concept id="GUID-577F42BA-299E-5071-8C7A-FA0CBADCECAE" xml:lang="en"><title>The

    13 types of array</title><shortdesc>Describes the types of array available.</shortdesc><prolog><metadata><keywords/></metadata></prolog><conbody>

    14 <section id="GUID-A39A5291-6177-4521-AB8F-65D3F09FC333"><title>General arrays of objects</title> <p>Six general types of

    15 array can be constructed:</p> <ul>

    16 <li id="GUID-37305910-8E80-5F8B-9511-2354BD66BD38"><p><codeph>CArrayFixFlat&lt;Class

    17 T&gt;</codeph>: an array of elements, all having the same length. It uses a flat

    18 array buffer implemented by a <codeph>CBufFlat</codeph> object. The array

    19 object itself is allocated on the heap.</p> </li>

    20 <li id="GUID-E0E535CE-F623-57C9-86DC-BC755E00FE3F"><p><codeph>CArrayFixSeg&lt;Class

    21 T&gt;</codeph>: an array of elements, all having the same length. It uses a segmented

    22 array buffer implemented by a <codeph>CBufSeg</codeph> object. The array object

    23 itself is allocated on the heap.</p> </li>

    24 <li id="GUID-BA0B6BF0-C156-596A-B63F-9A7D262C218E"><p><codeph>CArrayVarFlat&lt;Class

    25 T&gt;</codeph>: an array of elements having varying lengths. It uses a flat array

    26 buffer implemented by a <codeph>CBufFlat</codeph> object. The array object

    27 itself is allocated on the heap.</p> </li>

    28 <li id="GUID-3E74B298-B832-5404-9002-92E7CE8D3228"><p><codeph>CArrayVarSeg&lt;Class

    29 T&gt;</codeph>: an array of elements having varying lengths. It uses a segmented

    30 array buffer implemented by a <codeph>CBufSeg</codeph> object. The array object

    31 itself is allocated on the heap.</p> </li>

    32 <li id="GUID-3A949BDB-822A-59EE-8C15-E5FB3EBC8FAE"><p><codeph>CArrayPakFlat&lt;Class

    33 T&gt;</codeph>: an array of elements having varying lengths. It uses a flat array

    34 buffer implemented by a <codeph>CBufFlat</codeph> object. The length value

    35 of an element precedes the element itself within the array buffer. The array

    36 object itself is allocated on the heap.</p> </li>

    37 <li id="GUID-7B30A669-8BF5-5DDC-BDC2-2097C7631257"><p><codeph>RArray&lt;class

    38 T&gt;</codeph>: a simple array of elements, all having the same length. The array

    39 buffer is flat and is implemented by the array class as a simple piece of

    40 linear memory. The array object itself can be constructed on the program stack.</p> </li>

    41 </ul> </section>

    42 <section id="GUID-3A99B95E-EF5D-4E7E-B545-7A9E1FE12C14"><title>General arrays of pointers</title> <p>There are three arrays

    43 which can be used when the elements are <i>pointers</i> to <codeph>CBase</codeph> derived

    44 objects. They allow type-safe access to <codeph>CBase</codeph> derived objects:</p> <ul>

    45 <li id="GUID-F395B716-D47E-5915-834D-8B10C35BAC59"><p><codeph>CArrayPtrFlat&lt;class T&gt;</codeph>:

    46 an array of pointers using a flat array buffer implemented by a <codeph>CBufFlat</codeph> object.

    47 The array object itself is allocated on the heap.</p> </li>

    48 <li id="GUID-ECE75F75-0178-5F00-8EE3-1B2BD162B764"><p><codeph>CArrayPtrSeg&lt;class T&gt;</codeph>:

    49 an array of pointers using a segmented array buffer implemented by a <codeph>CBufSeg</codeph> object.

    50 The array object itself is allocated on the heap.</p> </li>

    51 <li id="GUID-F4AEDDAE-E8EA-571F-9089-BB736559FCE1"><p><codeph>RPointerArray&lt;class

    52 T&gt;</codeph>: a simple array of pointers using a flat array buffer implemented

    53 by the array class as a simple piece of linear memory. The array object itself

    54 can be constructed on the program stack.</p> </li>

    55 </ul> </section>

    56 <section id="GUID-039B6556-C13A-4DFF-A1A7-D11A3702FE46"><title>Specialised arrays</title> <p>There are two specialised arrays

    57 of <i>untyped</i> elements, all having the same length, which can be used

    58 as data members of a base class in a thin template class/base class pair.

    59 These classes are useful in situations where the type of elements forming

    60 the array cannot be known in advance:</p> <ul>

    61 <li id="GUID-2D1A46DD-FFA6-56FD-A0E4-9C4655B3B9C2"><p><codeph>CArrayFixFlat&lt;TAny&gt;</codeph>.

    62 An array of untyped elements all having the same length. It uses a flat array

    63 buffer implemented by a <codeph>CBufFlat</codeph> object.</p> </li>

    64 <li id="GUID-CBF3264E-DE5C-5FA3-B953-CF6F14208EEB"><p><codeph>CArrayFixSeg&lt;TAny&gt;</codeph>.

    65 An array of untyped elements all having the same length. It uses a segmented

    66 array buffer implemented by a <codeph>CBufSeg</codeph> object.</p> </li>

    67 </ul> <p>There are two specialised arrays of <i>untyped</i> elements, having

    68 varying lengths, which can be used as data members of a base class in a thin

    69 template class/base class pair. These classes are useful in situations where

    70 the type of element forming the array is known only at the time the class

    71 is created (i.e. at compile time):</p> <ul>

    72 <li id="GUID-D689224C-F6F2-5A82-9A90-091663814F86"><p><codeph>CArrayVar&lt;TAny&gt;</codeph>.

    73 An array of untyped elements with varying lengths.</p> </li>

    74 <li id="GUID-5E2E9D37-65E8-5804-BD5B-6A37703C745B"><p><codeph>CArrayPak&lt;TAny&gt;</codeph>.

    75 An array of packed (variable length) elements.</p> </li>

    76 </ul> <p>There are two template specialisations of <codeph>RArray&lt;class

    77 T&gt;</codeph>.</p> <ul>

    78 <li id="GUID-A4F7D38C-7AE6-5E6B-A36F-1D70624C3E45"><p><codeph>RArray&lt;TInt&gt;</codeph>.

    79 An array of signed integers</p> </li>

    80 <li id="GUID-AB865DDB-5522-5A36-9DBB-BB0D535A9B9F"><p><codeph>RArray&lt;TUint&gt;</codeph>.

    81 An array of signed integers.</p> </li>

    82 </ul> </section>

    83 </conbody></concept>