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    10 <!DOCTYPE concept

    11   PUBLIC "-//OASIS//DTD DITA Concept//EN" "concept.dtd">

    12 <concept id="GUID-D37E0579-0F3B-5EE4-8264-1358E493672B" xml:lang="en"><title>Array

    13 of variable length elements, flat buffer</title><shortdesc>Describes how elements of varying length are organised in the array

    14 buffer.</shortdesc><prolog><metadata><keywords/></metadata></prolog><conbody>

    15 <p>This is a <codeph>CArrayVarFlat&lt;class T&gt;</codeph> object whose

    16 elements can have different lengths. Although each element is a <codeph>class T</codeph> object,

    17 the length of that object can vary.</p>

    18 <p>In this type of array, each element occupies its own individual cell allocated

    19 from the heap. The array buffer contains fixed length data structures, one

    20 for each element, which are physically contiguous within the flat array buffer.

    21 Each fixed length data structure contains the length of an element (a <codeph>TInt</codeph> value)

    22 and a pointer to it. The structure itself is part of the implementation but

    23 occupies no more than eight bytes on 32-bit machines.</p>

    24 <p>A flat buffer always occupies a single cell allocated from the heap and

    25 is always extended by the process of reallocation. A flat array buffer is

    26 implemented using a <codeph>CBufFlat</codeph> object.</p>

    27 <p>The following diagram illustrates how elements are organised within the

    28 array buffer:</p>

    29 <fig id="GUID-2A857FBF-943D-5665-9999-BC27EA321F73">

    30 <image href="GUID-924E26D6-8B9D-5C76-AF61-7C5514BB3D78_d0e219442_href.png" placement="inline"/>

    31 </fig>

    32 <p>This kind of array is suitable for a small number of elements or for a

    33 moderately large but fixed maximum number of elements. It is not suitable

    34 for large arrays with a high turnover of elements. </p>

    35 <p>This class is immediately derived from the abstract templated base class <codeph>CArrayVar&lt;class T&gt;</codeph> which

    36 is itself derived from the abstract non-templated base class <codeph>CArrayVarBase</codeph>.</p>

    37 <section id="GUID-59ADA2D7-56B2-44C3-8E7C-A5DE5F0BBDBA"><title>See also</title> <p><xref href="GUID-112AAFA5-B4C9-5B62-A106-FB5097C13A0E.dita">Using

    38 Dynamic Buffers</xref>.</p> </section>

    39 </conbody></concept>