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<title>Design Rationale</title>
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<div class="titlepage"><div><div><h3 class="title">
<a name="array.rationale"></a>Design Rationale</h3></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 type="disc"><li>
<p>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 href="../boost/array.html" title="Class template array">boost::array</a></code>&lt;int,4&gt; a = { { 1, 2, 3 } };</pre>
<p>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 type="disc">
<li>No user-declared constructors.</li>
<li>No private or protected non-static data members.</li>
<li>No base classes.</li>
<li>No virtual functions.</li>
</ul></div>
<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 href="../boost/array.html" title="Class template array">boost::array</a></code>&lt;int,4&gt; 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>
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