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Fixed Andrei's Policy quote

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[SVN r25026]
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Dave Abrahams 2004-09-13 03:40:00 +00:00
parent fd599fe650
commit c0d7b1953f
1 changed files with 19 additions and 19 deletions
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@ -213,9 +213,9 @@ struct iterator_traits {
<h2><a name="tag_dispatching">Tag Dispatching</a></h2>
<p>A technique that often goes hand in hand with traits classes is tag
dispatching, which is a way of using function overloading to dispatch
based on properties of a type. A good example of this is the
<p>Tag dispatching is a way of using function overloading to
dispatch based on properties of a type, and is often used hand in
hand with traits classes. A good example of this synergy is the
implementation of the <a href=
"http://www.sgi.com/tech/stl/advance.html"><tt>std::advance()</tt></a>
function in the C++ Standard Library, which increments an iterator
@ -307,7 +307,7 @@ namespace std {
<h2><a name="type_generator">Type Generators</a></h2>
<p><b>Note:</b> The <i>type generator</i> concept has largely been
superseded by the more-refined notion of a <a href=
superseded by the more refined notion of a <a href=
"../libs/mpl/doc/ref/Metafunction.html"><i>metafunction</i></a>. See
<i><a href="http://www.boost-consulting.com/mplbook">C++ Template
Metaprogramming</a></i> for an in-depth discussion of metafunctions.</p>
@ -415,20 +415,20 @@ void tweak_all_widgets2(int arg)
<p>Policy classes have been explored in detail by <a href=
"http://www.moderncppdesign.com/">Andrei Alexandrescu</a> in <a href=
"http://www.cs.ualberta.ca/~hoover/cmput401/XP-Notes/xp-conf/Papers/7_3_Alexandrescu.pdf">
this paper</a>. He writes:</p>
"http://www.informit.com/articles/article.asp?p=167842">this chapter</a>
of his book, <i>Modern C++ Design</i>. He writes:</p>
<blockquote>
<p>Policy classes are implementations of punctual design choices. They
are inherited from, or contained within, other classes. They provide
different strategies under the same syntactic interface. A class using
policies is templated having one template parameter for each policy it
uses. This allows the user to select the policies needed.</p>
<p>In brief, policy-based class design fosters assembling a class with
complex behavior out of many little classes (called policies), each of
which takes care of only one behavioral or structural aspect. As the
name suggests, a policy establishes an interface pertaining to a
specific issue. You can implement policies in various ways as long as
you respect the policy interface.</p>
<p>The power of policy classes comes from their ability to combine
freely. By combining several policy classes in a template class with
multiple parameters, one achieves combinatorial behaviors with a linear
amount of code.</p>
<p>Because you can mix and match policies, you can achieve a
combinatorial set of behaviors by using a small core of elementary
components.</p>
</blockquote>
<p>Andrei's description of policy classes suggests that their power is
@ -460,15 +460,15 @@ void tweak_all_widgets2(int arg)
express or implied warranty, and with no claim as to its suitability for
any purpose.
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<!-- LocalWords: typename Alexandrescu templated Andrei's Abrahams memcpy int
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</p>
</body>
</html>