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<div class="titlepage"><div><div><h2 class="title" style="clear: both">
<a name="circular_buffer.rationale"></a><a class="link" href="rationale.html" title="Rationale">Rationale</a>
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<p>
      The basic motivation behind the <code class="computeroutput"><a class="link" href="../boost/circular_buffer.html" title="Class template circular_buffer">circular_buffer</a></code>
      was to create a container which would <span class="bold"><strong>work seamlessly
      with STL</strong></span>.
    </p>
<p>
      Additionally, the design of the <code class="computeroutput"><a class="link" href="../boost/circular_buffer.html" title="Class template circular_buffer">circular_buffer</a></code>
      was guided by the following principles:
    </p>
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
          Maximum <span class="emphasis"><em>efficiency</em></span> for envisaged applications.
        </li>
<li class="listitem">
          Suitable for <span class="emphasis"><em>general purpose use</em></span>.
        </li>
<li class="listitem">
          The behaviour of the buffer as <span class="emphasis"><em>intuitive</em></span> as possible.
        </li>
<li class="listitem">
          Suitable for <span class="emphasis"><em>specialization</em></span> by means of adaptors.
          (The <code class="computeroutput"><a class="link" href="../boost/circular_idm45717958544272.html" title="Class template circular_buffer_space_optimized">circular_buffer_space_optimized</a></code>
          is such an example of the adaptor.)
        </li>
<li class="listitem">
          Easy to <span class="emphasis"><em>debug</em></span>. (See Debug Support for details.)
        </li>
</ul></div>
<p>
      In order to achieve maximum efficiency, the <code class="computeroutput"><a class="link" href="../boost/circular_buffer.html" title="Class template circular_buffer">circular_buffer</a></code>
      and <code class="computeroutput"><a class="link" href="../boost/circular_idm45717958544272.html" title="Class template circular_buffer_space_optimized">circular_buffer_space_optimized</a></code>
      store their elements in a <span class="bold"><strong>contiguous region of memory</strong></span>,
      which then enables:
    </p>
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
          Use of fixed memory and no implicit or unexpected memory allocation.
        </li>
<li class="listitem">
          Fast constant-time insertion and removal of elements from the front and
          back.
        </li>
<li class="listitem">
          Fast constant-time random access of elements.
        </li>
<li class="listitem">
          Suitability for real-time and performance critical applications.
        </li>
</ul></div>
<p>
      Possible applications of the circular buffer include:
    </p>
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
          Storage of the <span class="emphasis"><em>most recently received samples</em></span>, overwriting
          the oldest as new samples arrive.
        </li>
<li class="listitem">
          As an underlying container for a <span class="emphasis"><em>bounded buffer</em></span> (see
          the Bounded Buffer example, code at <a href="../../../libs/circular_buffer/example/circular_buffer_bound_example.cpp" target="_top">circular_buffer_bound_example.cpp</a>).
        </li>
<li class="listitem">
          A kind of <span class="emphasis"><em>cache</em></span> storing a specified number of last
          inserted elements.
        </li>
<li class="listitem">
          Efficient fixed capacity <span class="emphasis"><em>FIFO (First In, First Out)</em></span>,
        </li>
<li class="listitem">
          Efficient fixed capacity <span class="emphasis"><em>LIFO (Last In, First Out)</em></span>
          queue which removes the oldest (inserted as first) elements when full.
        </li>
</ul></div>
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