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diff --git a/doc/html/array/rationale.html b/doc/html/array/rationale.html new file mode 100755 index 0000000000..847952d424 --- /dev/null +++ b/doc/html/array/rationale.html @@ -0,0 +1,81 @@ +<html> +<head> +<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII"> +<title>Design Rationale</title> +<link rel="stylesheet" href="../../../doc/src/boostbook.css" type="text/css"> +<meta name="generator" content="DocBook XSL Stylesheets V1.76.1"> +<link rel="home" href="../index.html" title="The Boost C++ Libraries BoostBook Documentation Subset"> +<link rel="up" href="../array.html" title="Chapter 3. Boost.Array"> +<link rel="prev" href="../boost/array.html" title="Class template array"> +<link rel="next" href="more/info.html" title="For more information..."> +</head> +<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"> +<table cellpadding="2" width="100%"><tr> +<td valign="top"><img alt="Boost C++ Libraries" width="277" height="86" src="../../../boost.png"></td> +<td align="center"><a href="../../../index.html">Home</a></td> +<td align="center"><a href="../../../libs/libraries.htm">Libraries</a></td> +<td align="center"><a href="http://www.boost.org/users/people.html">People</a></td> +<td align="center"><a href="http://www.boost.org/users/faq.html">FAQ</a></td> +<td align="center"><a href="../../../more/index.htm">More</a></td> +</tr></table> +<hr> +<div class="spirit-nav"> +<a accesskey="p" href="../boost/array.html"><img src="../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../array.html"><img src="../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../index.html"><img src="../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="more/info.html"><img src="../../../doc/src/images/next.png" alt="Next"></a> +</div> +<div class="section"> +<div class="titlepage"><div><div><h2 class="title" style="clear: both"> +<a name="array.rationale"></a>Design Rationale</h2></div></div></div> +<p>There was an important design tradeoff regarding the + constructors: We could implement array as an "aggregate" (see + Section 8.5.1, [dcl.init.aggr], of the C++ Standard). This would + mean: + </p> +<div class="itemizedlist"><ul class="itemizedlist" type="disc"><li class="listitem"> +<p class="simpara">An array can be initialized with a + brace-enclosing, comma-separated list of initializers for the + elements of the container, written in increasing subscript + order:</p> +<pre class="programlisting"><code class="computeroutput"><a class="link" href="../boost/array.html" title="Class template array">boost::array</a></code><int,4> a = { { 1, 2, 3 } };</pre> +<p class="simpara">Note that if there are fewer elements in the + initializer list, then each remaining element gets + default-initialized (thus, it has a defined value).</p> +</li></ul></div> +<p>However, this approach has its drawbacks: <span class="bold"><strong> passing no initializer list means that the elements + have an indetermined initial value</strong></span>, because the rule says + that aggregates may have: + </p> +<div class="itemizedlist"><ul class="itemizedlist" type="disc"> +<li class="listitem">No user-declared constructors.</li> +<li class="listitem">No private or protected non-static data members.</li> +<li class="listitem">No base classes.</li> +<li class="listitem">No virtual functions.</li> +</ul></div> +<p> + </p> +<p>Nevertheless, The current implementation uses this approach.</p> +<p>Note that for standard conforming compilers it is possible to + use fewer braces (according to 8.5.1 (11) of the Standard). That is, + you can initialize an array as follows:</p> +<pre class="programlisting"> +<code class="computeroutput"><a class="link" href="../boost/array.html" title="Class template array">boost::array</a></code><int,4> a = { 1, 2, 3 }; +</pre> +<p>I'd appreciate any constructive feedback. <span class="bold"><strong>Please note: I don't have time to read all boost + mails. Thus, to make sure that feedback arrives to me, please send + me a copy of each mail regarding this class.</strong></span></p> +<p>The code is provided "as is" without expressed or implied + warranty.</p> +</div> +<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> +<td align="left"></td> +<td align="right"><div class="copyright-footer">Copyright © 2001-2004 Nicolai M. Josuttis<p>Distributed under the Boost Software License, Version 1.0. + (See accompanying file <code class="filename">LICENSE_1_0.txt</code> or copy at + <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>) + </p> +</div></td> +</tr></table> +<hr> +<div class="spirit-nav"> +<a accesskey="p" href="../boost/array.html"><img src="../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../array.html"><img src="../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../index.html"><img src="../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="more/info.html"><img src="../../../doc/src/images/next.png" alt="Next"></a> +</div> +</body> +</html> |