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<section id="std.localization.facet.ctype" xreflabel="ctype">
<?dbhtml filename="ctype.html"?>
<sectioninfo>
<keywordset>
<keyword>
ISO C++
</keyword>
<keyword>
ctype
</keyword>
</keywordset>
</sectioninfo>
<title>ctype</title>
<section id="facet.ctype.impl">
<title>Implementation</title>
<section>
<title>Specializations</title>
<para>
For the required specialization codecvt<wchar_t, char, mbstate_t> ,
conversions are made between the internal character set (always UCS4
on GNU/Linux) and whatever the currently selected locale for the
LC_CTYPE category implements.
</para>
<para>
The two required specializations are implemented as follows:
</para>
<para>
<code>
ctype<char>
</code>
</para>
<para>
This is simple specialization. Implementing this was a piece of cake.
</para>
<para>
<code>
ctype<wchar_t>
</code>
</para>
<para>
This specialization, by specifying all the template parameters, pretty
much ties the hands of implementors. As such, the implementation is
straightforward, involving mcsrtombs for the conversions between char
to wchar_t and wcsrtombs for conversions between wchar_t and char.
</para>
<para>
Neither of these two required specializations deals with Unicode
characters.
</para>
</section>
</section>
<section id="facet.ctype.future">
<title>Future</title>
<itemizedlist>
<listitem>
<para>
How to deal with the global locale issue?
</para></listitem>
<listitem>
<para>
How to deal with different types than char, wchar_t? </para></listitem>
<listitem><para>
Overlap between codecvt/ctype: narrow/widen
</para></listitem>
<listitem>
<para>
Mask typedef in codecvt_base, argument types in codecvt. what
is know about this type?
</para></listitem>
<listitem>
<para>
Why mask* argument in codecvt?
</para></listitem>
<listitem>
<para>
Can this be made (more) generic? is there a simple way to
straighten out the configure-time mess that is a by-product of
this class?
</para></listitem>
<listitem>
<para>
Get the ctype<wchar_t>::mask stuff under control. Need to
make some kind of static table, and not do lookup every time
somebody hits the do_is... functions. Too bad we can't just
redefine mask for ctype<wchar_t>
</para></listitem>
<listitem>
<para>
Rename abstract base class. See if just smash-overriding is a
better approach. Clarify, add sanity to naming.
</para>
</listitem>
</itemizedlist>
</section>
<bibliography id="facet.ctype.biblio">
<title>Bibliography</title>
<biblioentry>
<title>
The GNU C Library
</title>
<author>
<surname>McGrath</surname>
<firstname>Roland</firstname>
</author>
<author>
<surname>Drepper</surname>
<firstname>Ulrich</firstname>
</author>
<copyright>
<year>2007</year>
<holder>FSF</holder>
</copyright>
<pagenums>Chapters 6 Character Set Handling and 7 Locales and Internationalization</pagenums>
</biblioentry>
<biblioentry>
<title>
Correspondence
</title>
<author>
<surname>Drepper</surname>
<firstname>Ulrich</firstname>
</author>
<copyright>
<year>2002</year>
<holder></holder>
</copyright>
</biblioentry>
<biblioentry>
<title>
ISO/IEC 14882:1998 Programming languages - C++
</title>
<copyright>
<year>1998</year>
<holder>ISO</holder>
</copyright>
</biblioentry>
<biblioentry>
<title>
ISO/IEC 9899:1999 Programming languages - C
</title>
<copyright>
<year>1999</year>
<holder>ISO</holder>
</copyright>
</biblioentry>
<biblioentry>
<biblioid class="uri">
<ulink url="http://www.unix.org/version3/ieee_std.html">
<citetitle>
The Open Group Base Specifications, Issue 6 (IEEE Std. 1003.1-2004)
</citetitle>
</ulink>
</biblioid>
<copyright>
<year>1999</year>
<holder>
The Open Group/The Institute of Electrical and Electronics Engineers, Inc.</holder>
</copyright>
</biblioentry>
<biblioentry>
<title>
The C++ Programming Language, Special Edition
</title>
<author>
<surname>Stroustrup</surname>
<firstname>Bjarne</firstname>
</author>
<copyright>
<year>2000</year>
<holder>Addison Wesley, Inc.</holder>
</copyright>
<pagenums>Appendix D</pagenums>
<publisher>
<publishername>
Addison Wesley
</publishername>
</publisher>
</biblioentry>
<biblioentry>
<title>
Standard C++ IOStreams and Locales
</title>
<subtitle>
Advanced Programmer's Guide and Reference
</subtitle>
<author>
<surname>Langer</surname>
<firstname>Angelika</firstname>
</author>
<author>
<surname>Kreft</surname>
<firstname>Klaus</firstname>
</author>
<copyright>
<year>2000</year>
<holder>Addison Wesley Longman, Inc.</holder>
</copyright>
<publisher>
<publishername>
Addison Wesley Longman
</publishername>
</publisher>
</biblioentry>
</bibliography>
</section>
|
