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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>
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<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>
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<li class="listitem">
Use of fixed memory and no implicit or unexpected memory allocation.
</li>
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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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<td align="right"><div class="copyright-footer">Copyright © 2003-2013 Jan Gaspar<p>
Distributed under the Boost Software License, Version 1.0. (See accompanying
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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