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diff --git a/doc/test/array.xml b/doc/test/array.xml new file mode 100644 index 0000000000..ce3f57e029 --- /dev/null +++ b/doc/test/array.xml @@ -0,0 +1,64 @@ +<section id="array.intro"> + <title>Introduction</title> + + <using-namespace name="boost"/> + <using-class name="array"/> + + <para>The C++ Standard Template Library STL as part of the C++ + Standard Library provides a framework for processing algorithms on + different kind of containers. However, ordinary arrays don't + provide the interface of STL containers (although, they provide + the iterator interface of STL containers).</para> + + <para>As replacement for ordinary arrays, the STL provides class + <code><classname>std::vector</classname></code>. However, + <code><classname>std::vector<></classname></code> provides + the semantics of dynamic arrays. Thus, it manages data to be able + to change the number of elements. This results in some overhead in + case only arrays with static size are needed.</para> + + <para>In his book, <emphasis>Generic Programming and the + STL</emphasis>, Matthew H. Austern introduces a useful wrapper + class for ordinary arrays with static size, called + <code>block</code>. It is safer and has no worse performance than + ordinary arrays. In <emphasis>The C++ Programming + Language</emphasis>, 3rd edition, Bjarne Stroustrup introduces a + similar class, called <code>c_array</code>, which I (<ulink + url="http://www.josuttis.com">Nicolai Josuttis</ulink>) present + slightly modified in my book <emphasis>The C++ Standard Library - + A Tutorial and Reference</emphasis>, called + <code>carray</code>. This is the essence of these approaches + spiced with many feedback from <ulink + url="http://www.boost.org">boost</ulink>.</para> + + <para>After considering different names, we decided to name this + class simply <code><classname>array</classname></code>.</para> + + <para>Note that this class is suggested to be part of the next + Technical Report, which will extend the C++ Standard (see + <ulink url="http://std.dkuug.dk/jtc1/sc22/wg21/docs/papers/2003/n1548.htm">http://std.dkuug.dk/jtc1/sc22/wg21/docs/papers/2003/n1548.htm</ulink>).</para> + + <para>Class <code><classname>array</classname></code> fulfills most + but not all of the requirements of "reversible containers" (see + Section 23.1, [lib.container.requirements] of the C++ + Standard). The reasons array is not an reversible STL container is + because: + <itemizedlist spacing="compact"> + <listitem><simpara>No constructors are provided.</simpara></listitem> + <listitem><simpara>Elements may have an undetermined initial value (see <xref linkend="array.rationale"/>).</simpara></listitem> + <listitem><simpara><functionname>swap</functionname>() has no constant complexity.</simpara></listitem> + <listitem><simpara><methodname>size</methodname>() is always constant, based on the second template argument of the type.</simpara></listitem> + <listitem><simpara>The container provides no allocator support.</simpara></listitem> + </itemizedlist> + </para> + + <para>It doesn't fulfill the requirements of a "sequence" (see Section 23.1.1, [lib.sequence.reqmts] of the C++ Standard), except that: + <itemizedlist spacing="compact"> + <listitem><simpara><methodname>front</methodname>() and <methodname>back</methodname>() are provided.</simpara></listitem> + <listitem><simpara><methodname>operator[]</methodname> and <methodname>at</methodname>() are provided.</simpara></listitem> + </itemizedlist> + </para> + </section> + + + |