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4  Localization
5  
6</th><td width="20%" align="right">��<a accesskey="n" href="codecvt.html">Next</a></td></tr></table><hr /></div><div class="chapter" title="Chapter��15.��Facets aka Categories"><div class="titlepage"><div><div><h2 class="title"><a id="manual.localization.facet"></a>Chapter��15.��Facets aka Categories</h2></div></div></div><div class="toc"><p><b>Table of Contents</b></p><dl><dt><span class="sect1"><a href="facets.html#manual.localization.facet.ctype">ctype</a></span></dt><dd><dl><dt><span class="sect2"><a href="facets.html#facet.ctype.impl">Implementation</a></span></dt><dt><span class="sect2"><a href="facets.html#facet.ctype.future">Future</a></span></dt></dl></dd><dt><span class="sect1"><a href="codecvt.html">codecvt</a></span></dt><dd><dl><dt><span class="sect2"><a href="codecvt.html#facet.codecvt.req">Requirements</a></span></dt><dt><span class="sect2"><a href="codecvt.html#facet.codecvt.design">Design</a></span></dt><dt><span class="sect2"><a href="codecvt.html#facet.codecvt.impl">Implementation</a></span></dt><dt><span class="sect2"><a href="codecvt.html#facet.codecvt.use">Use</a></span></dt><dt><span class="sect2"><a href="codecvt.html#facet.codecvt.future">Future</a></span></dt></dl></dd><dt><span class="sect1"><a href="messages.html">messages</a></span></dt><dd><dl><dt><span class="sect2"><a href="messages.html#facet.messages.req">Requirements</a></span></dt><dt><span class="sect2"><a href="messages.html#facet.messages.design">Design</a></span></dt><dt><span class="sect2"><a href="messages.html#facet.messages.impl">Implementation</a></span></dt><dt><span class="sect2"><a href="messages.html#facet.messages.use">Use</a></span></dt><dt><span class="sect2"><a href="messages.html#facet.messages.future">Future</a></span></dt></dl></dd></dl></div><div class="sect1" title="ctype"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a id="manual.localization.facet.ctype"></a>ctype</h2></div></div></div><div class="sect2" title="Implementation"><div class="titlepage"><div><div><h3 class="title"><a id="facet.ctype.impl"></a>Implementation</h3></div></div></div><div class="sect3" title="Specializations"><div class="titlepage"><div><div><h4 class="title"><a id="id602134"></a>Specializations</h4></div></div></div><p>
7For the required specialization codecvt&lt;wchar_t, char, mbstate_t&gt; ,
8conversions are made between the internal character set (always UCS4
9on GNU/Linux) and whatever the currently selected locale for the
10LC_CTYPE category implements.
11</p><p>
12The two required specializations are implemented as follows:
13</p><p>
14<code class="code">
15ctype&lt;char&gt;
16</code>
17</p><p>
18This is simple specialization. Implementing this was a piece of cake.
19</p><p>
20<code class="code">
21ctype&lt;wchar_t&gt;
22</code>
23</p><p>
24This specialization, by specifying all the template parameters, pretty
25much ties the hands of implementors. As such, the implementation is
26straightforward, involving mcsrtombs for the conversions between char
27to wchar_t and wcsrtombs for conversions between wchar_t and char.
28</p><p>
29Neither of these two required specializations deals with Unicode
30characters.
31</p></div></div><div class="sect2" title="Future"><div class="titlepage"><div><div><h3 class="title"><a id="facet.ctype.future"></a>Future</h3></div></div></div><div class="itemizedlist"><ul class="itemizedlist" type="disc"><li class="listitem"><p>
32   How to deal with the global locale issue? 
33   </p></li><li class="listitem"><p> 
34   How to deal with different types than char, wchar_t? </p></li><li class="listitem"><p>
35   Overlap between codecvt/ctype: narrow/widen 
36   </p></li><li class="listitem"><p> 
37       Mask typedef in codecvt_base, argument types in codecvt.  what
38       is know about this type? 
39   </p></li><li class="listitem"><p> 
40   Why mask* argument in codecvt?
41   </p></li><li class="listitem"><p>
42       Can this be made (more) generic? is there a simple way to
43       straighten out the configure-time mess that is a by-product of
44       this class?  
45   </p></li><li class="listitem"><p> 
46       Get the ctype&lt;wchar_t&gt;::mask stuff under control. Need to
47       make some kind of static table, and not do lookup every time
48       somebody hits the do_is... functions. Too bad we can't just
49       redefine mask for ctype&lt;wchar_t&gt; 
50   </p></li><li class="listitem"><p> 
51       Rename abstract base class. See if just smash-overriding is a
52       better approach. Clarify, add sanity to naming.
53     </p></li></ul></div></div><div class="bibliography" title="Bibliography"><div class="titlepage"><div><div><h3 class="title"><a id="facet.ctype.biblio"></a>Bibliography</h3></div></div></div><div class="biblioentry" title="The GNU C Library"><a id="id721212"></a><p><span class="title"><i>
54      The GNU C Library
55    </i>. </span><span class="author"><span class="firstname">Roland</span> <span class="surname">McGrath</span>. </span><span class="author"><span class="firstname">Ulrich</span> <span class="surname">Drepper</span>. </span><span class="copyright">Copyright �� 2007 FSF. </span><span class="pagenums">Chapters 6  Character Set Handling and 7 Locales and Internationalization. </span></p></div><div class="biblioentry" title="Correspondence"><a id="id611041"></a><p><span class="title"><i>
56      Correspondence
57    </i>. </span><span class="author"><span class="firstname">Ulrich</span> <span class="surname">Drepper</span>. </span><span class="copyright">Copyright �� 2002 . </span></p></div><div class="biblioentry" title="ISO/IEC 14882:1998 Programming languages - C++"><a id="id612309"></a><p><span class="title"><i>
58      ISO/IEC 14882:1998 Programming languages - C++
59    </i>. </span><span class="copyright">Copyright �� 1998 ISO. </span></p></div><div class="biblioentry" title="ISO/IEC 9899:1999 Programming languages - C"><a id="id612328"></a><p><span class="title"><i>
60      ISO/IEC 9899:1999 Programming languages - C
61    </i>. </span><span class="copyright">Copyright �� 1999 ISO. </span></p></div><div class="biblioentry" title="The Open Group Base Specifications, Issue 6 (IEEE Std. 1003.1-2004)"><a id="id626861"></a><p><span class="title"><i>
62      The Open Group Base Specifications, Issue 6 (IEEE Std. 1003.1-2004)
63    </i>. </span><span class="copyright">Copyright �� 1999 
64      The Open Group/The Institute of Electrical and Electronics Engineers, Inc.. </span><span class="biblioid">
65      <a class="ulink" href="http://www.unix.org/version3/ieee_std.html" target="_top">
66      </a>
67    . </span></p></div><div class="biblioentry" title="The C++ Programming Language, Special Edition"><a id="id626888"></a><p><span class="title"><i>
68      The C++ Programming Language, Special Edition
69    </i>. </span><span class="author"><span class="firstname">Bjarne</span> <span class="surname">Stroustrup</span>. </span><span class="copyright">Copyright �� 2000 Addison Wesley, Inc.. </span><span class="pagenums">Appendix D. </span><span class="publisher"><span class="publishername">
70	Addison Wesley
71      . </span></span></p></div><div class="biblioentry" title="Standard C++ IOStreams and Locales"><a id="id655841"></a><p><span class="title"><i>
72      Standard C++ IOStreams and Locales
73    </i>. </span><span class="subtitle">
74      Advanced Programmer's Guide and Reference
75    . </span><span class="author"><span class="firstname">Angelika</span> <span class="surname">Langer</span>. </span><span class="author"><span class="firstname">Klaus</span> <span class="surname">Kreft</span>. </span><span class="copyright">Copyright �� 2000 Addison Wesley Longman, Inc.. </span><span class="publisher"><span class="publishername">
76	Addison Wesley Longman
77      . </span></span></p></div></div></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="locales.html">Prev</a>��</td><td width="20%" align="center"><a accesskey="u" href="localization.html">Up</a></td><td width="40%" align="right">��<a accesskey="n" href="codecvt.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">Chapter��14.��Locales��</td><td width="20%" align="center"><a accesskey="h" href="../spine.html">Home</a></td><td width="40%" align="right" valign="top">��codecvt</td></tr></table></div></body></html>
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