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  28 <a name="circular_buffer.rationale"></a><a class="link" href="rationale.html" title="Rationale">Rationale</a>
  29 </h2></div></div></div>
  30 <p>
  31       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>
  32       was to create a container which would <span class="bold"><strong>work seamlessly
  33       with STL</strong></span>.
  34     </p>
  35 <p>
  36       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>
  37       was guided by the following principles:
  38     </p>
  39 <div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
  40 <li class="listitem">
  41           Maximum <span class="emphasis"><em>efficiency</em></span> for envisaged applications.
  42         </li>
  43 <li class="listitem">
  44           Suitable for <span class="emphasis"><em>general purpose use</em></span>.
  45         </li>
  46 <li class="listitem">
  47           The behaviour of the buffer as <span class="emphasis"><em>intuitive</em></span> as possible.
  48         </li>
  49 <li class="listitem">
  50           Suitable for <span class="emphasis"><em>specialization</em></span> by means of adaptors.
  51           (The <code class="computeroutput"><a class="link" href="../boost/circular_buffe_idp26541888.html" title="Class template circular_buffer_space_optimized">circular_buffer_space_optimized</a></code>
  52           is such an example of the adaptor.)
  53         </li>
  54 <li class="listitem">
  55           Easy to <span class="emphasis"><em>debug</em></span>. (See Debug Support for details.)
  56         </li>
  57 </ul></div>
  58 <p>
  59       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>
  60       and <code class="computeroutput"><a class="link" href="../boost/circular_buffe_idp26541888.html" title="Class template circular_buffer_space_optimized">circular_buffer_space_optimized</a></code>
  61       store their elements in a <span class="bold"><strong>contiguous region of memory</strong></span>,
  62       which then enables:
  63     </p>
  64 <div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
  65 <li class="listitem">
  66           Use of fixed memory and no implicit or unexpected memory allocation.
  67         </li>
  68 <li class="listitem">
  69           Fast constant-time insertion and removal of elements from the front and
  70           back.
  71         </li>
  72 <li class="listitem">
  73           Fast constant-time random access of elements.
  74         </li>
  75 <li class="listitem">
  76           Suitability for real-time and performance critical applications.
  77         </li>
  78 </ul></div>
  79 <p>
  80       Possible applications of the circular buffer include:
  81     </p>
  82 <div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
  83 <li class="listitem">
  84           Storage of the <span class="emphasis"><em>most recently received samples</em></span>, overwriting
  85           the oldest as new samples arrive.
  86         </li>
  87 <li class="listitem">
  88           As an underlying container for a <span class="emphasis"><em>bounded buffer</em></span> (see
  89           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>).
  90         </li>
  91 <li class="listitem">
  92           A kind of <span class="emphasis"><em>cache</em></span> storing a specified number of last
  93           inserted elements.
  94         </li>
  95 <li class="listitem">
  96           Efficient fixed capacity <span class="emphasis"><em>FIFO (First In, First Out)</em></span>,
  97         </li>
  98 <li class="listitem">
  99           Efficient fixed capacity <span class="emphasis"><em>LIFO (Last In, First Out)</em></span>
 100           queue which removes the oldest (inserted as first) elements when full.
 101         </li>
 102 </ul></div>
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 106 <td align="right"><div class="copyright-footer">Copyright &#169; 2003-2013 Jan Gaspar<p>
 107         Distributed under the Boost Software License, Version 1.0. (See accompanying
 108         file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
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