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diff --git a/libstdc++-v3/doc/html/manual/support.html b/libstdc++-v3/doc/html/manual/support.html new file mode 100644 index 000000000..39c8185c6 --- /dev/null +++ b/libstdc++-v3/doc/html/manual/support.html @@ -0,0 +1,130 @@ +<?xml version="1.0" encoding="UTF-8" standalone="no"?> +<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd"> +<html xmlns="http://www.w3.org/1999/xhtml"><head><title>Chapter 4. Support</title><meta name="generator" content="DocBook XSL-NS Stylesheets V1.76.1"/><meta name="keywords" content=" ISO C++ , library "/><link rel="home" href="../spine.html" title="The GNU C++ Library"/><link rel="up" href="bk01pt02.html" title="Part II. Standard Contents"/><link rel="prev" href="bk01pt02.html" title="Part II. Standard Contents"/><link rel="next" href="dynamic_memory.html" title="Dynamic Memory"/></head><body><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">Chapter 4. + Support + +</th></tr><tr><td align="left"><a accesskey="p" href="bk01pt02.html">Prev</a> </td><th width="60%" align="center">Part II. + Standard Contents + </th><td align="right"> <a accesskey="n" href="dynamic_memory.html">Next</a></td></tr></table><hr/></div><div class="chapter" title="Chapter 4. Support"><div class="titlepage"><div><div><h2 class="title"><a id="std.support"/>Chapter 4. + Support + <a id="id471617" class="indexterm"/> +</h2></div></div></div><div class="toc"><p><strong>Table of Contents</strong></p><dl><dt><span class="section"><a href="support.html#std.support.types">Types</a></span></dt><dd><dl><dt><span class="section"><a href="support.html#std.support.types.fundamental">Fundamental Types</a></span></dt><dt><span class="section"><a href="support.html#std.support.types.numeric_limits">Numeric Properties</a></span></dt><dt><span class="section"><a href="support.html#std.support.types.null">NULL</a></span></dt></dl></dd><dt><span class="section"><a href="dynamic_memory.html">Dynamic Memory</a></span></dt><dt><span class="section"><a href="termination.html">Termination</a></span></dt><dd><dl><dt><span class="section"><a href="termination.html#support.termination.handlers">Termination Handlers</a></span></dt><dt><span class="section"><a href="termination.html#support.termination.verbose">Verbose Terminate Handler</a></span></dt></dl></dd></dl></div><p> + This part deals with the functions called and objects created + automatically during the course of a program's existence. + </p><p> + While we can't reproduce the contents of the Standard here (you + need to get your own copy from your nation's member body; see our + homepage for help), we can mention a couple of changes in what + kind of support a C++ program gets from the Standard Library. + </p><div class="section" title="Types"><div class="titlepage"><div><div><h2 class="title"><a id="std.support.types"/>Types</h2></div></div></div><div class="section" title="Fundamental Types"><div class="titlepage"><div><div><h3 class="title"><a id="std.support.types.fundamental"/>Fundamental Types</h3></div></div></div><p> + C++ has the following builtin types: + </p><div class="itemizedlist"><ul class="itemizedlist"><li class="listitem"><p> + char + </p></li><li class="listitem"><p> + signed char + </p></li><li class="listitem"><p> + unsigned char + </p></li><li class="listitem"><p> + signed short + </p></li><li class="listitem"><p> + signed int + </p></li><li class="listitem"><p> + signed long + </p></li><li class="listitem"><p> + unsigned short + </p></li><li class="listitem"><p> + unsigned int + </p></li><li class="listitem"><p> + unsigned long + </p></li><li class="listitem"><p> + bool + </p></li><li class="listitem"><p> + wchar_t + </p></li><li class="listitem"><p> + float + </p></li><li class="listitem"><p> + double + </p></li><li class="listitem"><p> + long double + </p></li></ul></div><p> + These fundamental types are always available, without having to + include a header file. These types are exactly the same in + either C++ or in C. + </p><p> + Specializing parts of the library on these types is prohibited: + instead, use a POD. + </p></div><div class="section" title="Numeric Properties"><div class="titlepage"><div><div><h3 class="title"><a id="std.support.types.numeric_limits"/>Numeric Properties</h3></div></div></div><p> + The header <code class="filename">limits</code> defines + traits classes to give access to various implementation + defined-aspects of the fundamental types. The traits classes -- + fourteen in total -- are all specializations of the template class + <code class="classname">numeric_limits</code>, documented <a class="link" href="http://gcc.gnu.org/onlinedocs/libstdc++/latest-doxygen/a00593.html">here</a> + and defined as follows: + </p><pre class="programlisting"> + template<typename T> + struct class + { + static const bool is_specialized; + static T max() throw(); + static T min() throw(); + + static const int digits; + static const int digits10; + static const bool is_signed; + static const bool is_integer; + static const bool is_exact; + static const int radix; + static T epsilon() throw(); + static T round_error() throw(); + + static const int min_exponent; + static const int min_exponent10; + static const int max_exponent; + static const int max_exponent10; + + static const bool has_infinity; + static const bool has_quiet_NaN; + static const bool has_signaling_NaN; + static const float_denorm_style has_denorm; + static const bool has_denorm_loss; + static T infinity() throw(); + static T quiet_NaN() throw(); + static T denorm_min() throw(); + + static const bool is_iec559; + static const bool is_bounded; + static const bool is_modulo; + + static const bool traps; + static const bool tinyness_before; + static const float_round_style round_style; + }; + </pre></div><div class="section" title="NULL"><div class="titlepage"><div><div><h3 class="title"><a id="std.support.types.null"/>NULL</h3></div></div></div><p> + The only change that might affect people is the type of + <code class="constant">NULL</code>: while it is required to be a macro, + the definition of that macro is <span class="emphasis"><em>not</em></span> allowed + to be <code class="constant">(void*)0</code>, which is often used in C. + </p><p> + For <span class="command"><strong>g++</strong></span>, <code class="constant">NULL</code> is + <code class="code">#define</code>'d to be + <code class="constant">__null</code>, a magic keyword extension of + <span class="command"><strong>g++</strong></span>. + </p><p> + The biggest problem of #defining <code class="constant">NULL</code> to be + something like <span class="quote">“<span class="quote">0L</span>”</span> is that the compiler will view + that as a long integer before it views it as a pointer, so + overloading won't do what you expect. (This is why + <span class="command"><strong>g++</strong></span> has a magic extension, so that + <code class="constant">NULL</code> is always a pointer.) + </p><p>In his book <a class="link" href="http://www.awprofessional.com/titles/0-201-92488-9/"><span class="emphasis"><em>Effective + C++</em></span></a>, Scott Meyers points out that the best way + to solve this problem is to not overload on pointer-vs-integer + types to begin with. He also offers a way to make your own magic + <code class="constant">NULL</code> that will match pointers before it + matches integers. + </p><p>See + <a class="link" href="http://www.awprofessional.com/titles/0-201-31015-5/">the + Effective C++ CD example</a> + </p></div></div></div><div class="navfooter"><hr/><table width="100%" summary="Navigation footer"><tr><td align="left"><a accesskey="p" href="bk01pt02.html">Prev</a> </td><td align="center"><a accesskey="u" href="bk01pt02.html">Up</a></td><td align="right"> <a accesskey="n" href="dynamic_memory.html">Next</a></td></tr><tr><td align="left" valign="top">Part II. + Standard Contents + </td><td align="center"><a accesskey="h" href="../spine.html">Home</a></td><td align="right" valign="top"> Dynamic Memory</td></tr></table></div></body></html> |