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<td align="center"><a href="">Libraries</a></td>
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</div>
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<div class="section">
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<div class="titlepage"><div><div><h2 class="title" style="clear: both">
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<a name="safe_numerics.introduction"></a>Introduction</h2></div></div></div>
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<div class="toc"><dl>
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<dt><span class="section"><a href="introduction.html#idm449651883776">Problem</a></span></dt>
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<dt><span class="section"><a href="introduction.html#idm449651880544">Solution</a></span></dt>
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<dt><span class="section"><a href="introduction.html#idm449651877232">Requirements</a></span></dt>
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</dl></div>
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<div class="section">
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<div class="titlepage"><div><div><h3 class="title">
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<a name="idm449651883776"></a>Problem</h3></div></div></div>
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<p>Arithmetic operations in C++ are NOT guarenteed to yield a correct
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mathematical result. This feature is inherited from the early days of C.
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The behavior of <code class="computeroutput">int</code>, <code class="computeroutput">unsigned int</code> and others
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were designed to map closely to the underlying hardware. Computer hardware
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implements these types as a fixed number of bits. When the result of
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arithmetic operations exceeds this number of bits, the result is undefined
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and usually not what the programmer intended. It is incumbent up the C/C++
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programmer to guarentee that this behavior does not result in incorrect
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behavior of the program. There are no language facilities which do this.
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They have to be explicitly addressed in the program code. This is
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exceeding tedious and laborious for a programmer to do. Besides, adding
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this code would introduce another source of errors.</p>
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</div>
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<div class="section">
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<div class="titlepage"><div><div><h3 class="title">
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<a name="idm449651880544"></a>Solution</h3></div></div></div>
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<p>This library implements special versions of int, unsigned, etc.
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which behave exactly like the original ones EXCEPT that the results of
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these operations are checked to be sure any possible errors resulting from
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undefined arithmetic behavior are trapped at compile time (if possible) or
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at runtime.</p>
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<p>In addition to eliminating undefined behavior from primitive integer
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types, we define new data types <code class="computeroutput">safe_signed_range<MIN,
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MAX></code> and <code class="computeroutput">safe_unsigned_range<MIN, MAX></code> which
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will throw an exception if an attempt is made to store a result which is
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outside the closed range [MIN, MAX].</p>
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</div>
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<div class="section">
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<div class="titlepage"><div><div><h3 class="title">
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<a name="idm449651877232"></a>Requirements</h3></div></div></div>
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<p>This library is is composed entirely of C++ Headers. I requires a
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compiler compatible with the C++11 standard.</p>
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<p>The following Boost Libraries must be installed in order to use this
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library</p>
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<div class="itemizedlist"><ul class="itemizedlist" type="disc">
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<li class="listitem"><p>mpl</p></li>
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<li class="listitem"><p>integer</p></li>
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<li class="listitem"><p>limits</p></li>
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<li class="listitem"><p>config</p></li>
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<li class="listitem"><p>concept checking</p></li>
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<li class="listitem"><p>type traits</p></li>
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<li class="listitem"><p>integer traits</p></li>
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</ul></div>
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</div>
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</div>
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<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
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<td align="left"></td>
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<td align="right"><div class="copyright-footer">Copyright © 2012 Robert Ramey<p><a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt">Subject to Boost Software License</a></p>
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</div></td>
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