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4<section id="safe_numerics.notes">
5  <title>Background</title>
6
7  <para>This library started out as a re-implementation of the facilities
8  provided by <ulink url="http://safeint.codeplex.com">David LeBlanc's SafeInt
9  Library</ulink>. I found this library to be well done in every way. My main
10  usage was to run unit tests for my embedded systems projects on my PC.
11  Still, from my perspective it had a few issues.</para>
12
13  <itemizedlist>
14    <listitem>
15      <para>It was a lot of code in one header - 6400 lines. Very unwieldy to
16      understand, modify and maintain.</para>
17    </listitem>
18
19    <listitem>
20      <para>I couldn't find separate documentation other than that in the
21      header file.</para>
22    </listitem>
23
24    <listitem>
25      <para>It didn't use <ulink url="http://www.boost.org">Boost</ulink>
26      conventions for naming.</para>
27    </listitem>
28
29    <listitem>
30      <para>It required porting to different compilers.</para>
31    </listitem>
32
33    <listitem>
34      <para>It had a very long license associated with it.</para>
35    </listitem>
36
37    <listitem>
38      <para>I could find no test suite for the library.</para>
39    </listitem>
40  </itemizedlist>
41
42  <para>Using later versions of C++ and the its standard library, template
43  metaprogramming and <ulink url="http://www.boost.org">Boost
44  libraries</ulink> I managed to (re)implement similar functionality in under
45  2000 ? lines of code. I promoted this version as a possible submission to
46  the Boost. The feedback I received convinced me that no such library would
47  be considered acceptable to the large majority of C++ programmers. It seems
48  that the desire for maximum performance overrides any requirement that a
49  program be known to be free of bugs. By this time I had a better idea of the
50  opportunities available with the latest version of C++ (C++14) and resolved
51  to address this issue by creating a library which would provide all the
52  facilities of safe numerics at minimal runtime cost. The result is what you
53  see here. The library now consists of 7000 lines of code, approximately 50
54  separate tests and more than 60 pages of documentation and examples.</para>
55
56  <para>Since I wrote the above, I've been contacted by David LeBlanc. He's
57  been updating his package and informs me that the latest
58  version:<itemizedlist>
59      <listitem>
60        <para>SafeInt does not require porting for different compilers, is
61        fully supported on gcc, clang, and Visual Studio.</para>
62      </listitem>
63
64      <listitem>
65        <para>The license has been changed from MS-PL to MIT license.</para>
66      </listitem>
67
68      <listitem>
69        <para>The library has had a test suite since before it was public, and
70        is now located here:</para>
71      </listitem>
72
73      <listitem>
74        <para>SafeInt also has no external dependencies other than standard
75        library files, and doesn't need anything else installed to
76        work.</para>
77      </listitem>
78    </itemizedlist></para>
79
80  <para>His current package can now be found at in <ulink
81  url="https://github.com/dcleblanc/SafeInt">github</ulink>.</para>
82</section>
83