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diff --git a/libstdc++-v3/docs/html/22_locale/howto.html b/libstdc++-v3/docs/html/22_locale/howto.html index d8ada0464b1..d6a340c9e54 100644 --- a/libstdc++-v3/docs/html/22_locale/howto.html +++ b/libstdc++-v3/docs/html/22_locale/howto.html @@ -1,13 +1,17 @@ -<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0//EN"> -<html> +<?xml version="1.0" encoding="ISO-8859-1"?> +<!DOCTYPE html + PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" + "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> + +<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en"> <head> - <meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1"> - <meta name="AUTHOR" content="pme@gcc.gnu.org (Phil Edwards)"> - <meta name="KEYWORDS" content="HOWTO, libstdc++, GCC, g++, libg++, STL"> - <meta name="DESCRIPTION" content="HOWTO for the libstdc++ chapter 22."> - <meta name="GENERATOR" content="vi and eight fingers"> + <meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" /> + <meta name="AUTHOR" content="pme@gcc.gnu.org (Phil Edwards)" /> + <meta name="KEYWORDS" content="HOWTO, libstdc++, GCC, g++, libg++, STL" /> + <meta name="DESCRIPTION" content="HOWTO for the libstdc++ chapter 22." /> + <meta name="GENERATOR" content="vi and eight fingers" /> <title>libstdc++-v3 HOWTO: Chapter 22</title> -<link rel="StyleSheet" href="../lib3styles.css"> +<link rel="StyleSheet" href="../lib3styles.css" /> </head> <body> @@ -16,39 +20,40 @@ <p>Chapter 22 deals with the C++ localization facilities. </p> <!-- I wanted to write that sentence in something requiring an exotic font, - like Cryllic or Kanji. Probably more work than such cuteness is worth, + like Cyrllic or Kanji. Probably more work than such cuteness is worth, but I still think it'd be funny. --> <!-- ####################################################### --> -<hr> +<hr /> <h1>Contents</h1> <ul> - <li><a href="#1">class locale</a> - <li><a href="#2">class codecvt</a> - <li><a href="#3">class ctype</a> - <li><a href="#4">class messages</a> - <li><a href="#5">Bjarne Stroustrup on Locales</a> - <li><a href="#6">Nathan Myers on Locales</a> - <li><a href="#7">Correct Transformations</a> + <li><a href="#1">class locale</a></li> + <li><a href="#2">class codecvt</a></li> + <li><a href="#3">class ctype</a></li> + <li><a href="#4">class messages</a></li> + <li><a href="#5">Bjarne Stroustrup on Locales</a></li> + <li><a href="#6">Nathan Myers on Locales</a></li> + <li><a href="#7">Correct Transformations</a></li> </ul> <!-- ####################################################### --> -<hr> +<hr /> <h2><a name="1">class locale</a></h2> <p>Notes made during the implementation of locales can be found <a href="locale.html">here</a>. </p> -<hr> +<hr /> <h2><a name="2">class codecvt</a></h2> <p>Notes made during the implementation of codecvt can be found <a href="codecvt.html">here</a>. </p> <p>The following is the abstract from the implementation notes: + </p> <blockquote> The standard class codecvt attempts to address conversions between different character encoding schemes. In particular, the standard @@ -64,21 +69,20 @@ the required specializations for wide and narrow characters and the implementation-provided extended functionality are given. </blockquote> - </p> -<hr> +<hr /> <h2><a name="3">class ctype</a></h2> <p>Notes made during the implementation of ctype can be found <a href="ctype.html">here</a>. </p> -<hr> +<hr /> <h2><a name="4">class messages</a></h2> <p>Notes made during the implementation of messages can be found <a href="messages.html">here</a>. </p> -<hr> +<hr /> <h2><a name="5">Stroustrup on Locales</a></h2> <p>Dr. Bjarne Stroustrup has released a <a href="http://www.research.att.com/~bs/3rd_loc0.html">pointer</a> @@ -88,22 +92,22 @@ description of locales and how to use them. </p> <p>He also writes: + </p> <blockquote><em> Please note that I still consider this detailed description of locales beyond the needs of most C++ programmers. It is written with experienced programmers in mind and novices will do best to avoid it. </em></blockquote> - </p> -<hr> +<hr /> <h2><a name="6">Nathan Myers on Locales</a></h2> <p>An article entitled "The Standard C++ Locale" was published in Dr. Dobb's Journal and can be found <a href="http://www.cantrip.org/locale.html">here</a>. </p> -<hr> +<hr /> <h2><a name="7">Correct Transformations</a></h2> <!-- Jumping directly to here from chapter 21. --> <p>A very common question on newsgroups and mailing lists is, "How @@ -131,6 +135,7 @@ is created. Then member functions of that locale are called to perform minor tasks. Continuing the example from Chapter 21, we wish to use the following convenience functions: + </p> <pre> namespace std { template <class charT> @@ -140,6 +145,7 @@ charT tolower (charT c, const locale& loc) const; }</pre> + <p> This function extracts the appropriate "facet" from the locale <em>loc</em> and calls the appropriate member function of that facet, passing <em>c</em> as its argument. The resulting character @@ -154,6 +160,7 @@ parameter. So we write simple wrapper structs to handle that. </p> <p>The next-to-final version of the code started in Chapter 21 looks like: + </p> <pre> #include <iterator> // for back_inserter #include <locale> @@ -161,45 +168,43 @@ #include <algorithm> #include <cctype> // old <ctype.h> - struct Toupper + struct ToUpper { - Toupper (std::locale const& l) : loc(l) {;} - char operator() (char c) { return std::toupper(c,loc); } + ToUpper(std::locale const& l) : loc(l) {;} + char operator() (char c) const { return std::toupper(c,loc); } private: std::locale const& loc; }; - struct Tolower + struct ToLower { - Tolower (std::locale const& l) : loc(l) {;} - char operator() (char c) { return std::tolower(c,loc); } + ToLower(std::locale const& l) : loc(l) {;} + char operator() (char c) const { return std::tolower(c,loc); } private: std::locale const& loc; }; int main () { - std::string s ("Some Kind Of Initial Input Goes Here"); - Toupper up ( std::locale("C") ); - Tolower down ( std::locale("C") ); + std::string s("Some Kind Of Initial Input Goes Here"); + std::locale loc_c("C"); + ToUpper up(loc_c); + ToLower down(loc_c); - // Change everything into upper case - std::transform (s.begin(), s.end(), s.begin(), - up - ); + // Change everything into upper case. + std::transform(s.begin(), s.end(), s.begin(), up); - // Change everything into lower case - std::transform (s.begin(), s.end(), s.begin(), - down - ); + // Change everything into lower case. + std::transform(s.begin(), s.end(), s.begin(), down); // Change everything back into upper case, but store the - // result in a different string + // result in a different string. std::string capital_s; - std::transform (s.begin(), s.end(), std::back_inserter(capital_s), - up - ); + std::transform(s.begin(), s.end(), std::back_inserter(capital_s), up); }</pre> + <p>The <code>ToUpper</code> and <code>ToLower</code> structs can be + generalized for other character types by making <code>operator()</code> + a member function template. </p> <p>The final version of the code uses <code>bind2nd</code> to eliminate the wrapper structs, but the resulting code is tricky. I have not @@ -210,7 +215,7 @@ <!-- ####################################################### --> -<hr> +<hr /> <p class="fineprint"><em> See <a href="../17_intro/license.html">license.html</a> for copying conditions. Comments and suggestions are welcome, and may be sent to |