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- <h4>Arrays</h4>
- <div> An <i>array</i> is a data structure consisting of a two-element <i>tuple</i>.
- The first element is the number of elements in the <i>array</i>.
- The second element is another <i>tuple</i> of the elements in the <i>array</i>.
- For example, </div>
- <div class="code"> (<i>3</i>, (<i>a</i>, <i>b</i>, <i>c</i>)) </div>
- <div> ...is an <i>array</i> of <i>3</i> elements--<i>a</i>, <i>b</i>, and
- <i>c</i>. </div>
- <div> The primary strength of <i>arrays</i> is that they store their own
- size. Because of this, access to elements does not require the
- size. It only requires that an element exists at a certain index. </div>
- <div> This allows macro parameters to be variable in size and allows data
- states to change size without the user explicitly keeping track of the
- size independently.<br>
- <br>
- An <i>array </i>can be empty and have no elements. An empty array has a
- 0 size. The notation for an empty array is '(0,())'.<br>
- <br>
- <span style="font-style: italic;"> </span></div>
- <div>With variadic macro support a <i>tuple </i>has all of the
- functionality as an <i>array</i>, knows its own size, and is easier
- syntactically to use. Because of that an <i>array</i> should be used, as
- opposed to a <i>tuple</i>, only if your compiler does not support
- variadic macros. The only advantage an <i>array </i>has over a <i>tuple
- </i>is that an <i>array </i>can be empty while a <i>tuple </i>always
- has at least one element and therefore can never have a size of 0.<br>
- <br>
- Elements of an <i>array</i> can be extracted with <b>BOOST_PP_ARRAY_ELEM</b>,
- an <i>array's</i> size can be extracted with <b>BOOST_PP_ARRAY_SIZE</b>,
- and an <i>array</i> can be converted to the more primitive <i>tuple</i>
- data structure with <b>BOOST_PP_ARRAY_DATA</b>. </div>
- <h4>Primitives</h4>
- <ul>
- <li><a href="../ref/array_data.html">BOOST_PP_ARRAY_DATA</a></li>
- <li><a href="../ref/array_elem.html">BOOST_PP_ARRAY_ELEM</a></li>
- <li><a href="../ref/array_size.html">BOOST_PP_ARRAY_SIZE</a></li>
- </ul>
- <hr size="1">
- <div style="margin-left: 0px;"> <i>© Copyright <a href="http://www.housemarque.com"
- target="_top">Housemarque Oy</a> 2002</i> <br>
- <i>© Copyright Paul Mensonides 2002</i> </div>
- <div style="margin-left: 0px;">
- <p><small>Distributed under the Boost Software License, Version 1.0. (See
- accompanying file <a href="../../../../LICENSE_1_0.txt">LICENSE_1_0.txt</a>
- or copy at <a href="http://www.boost.org/LICENSE_1_0.txt">www.boost.org/LICENSE_1_0.txt</a>)</small></p>
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