diff options
Diffstat (limited to 'gcc-4.4.3/libstdc++-v3/doc/html/manual/pairs.html')
-rw-r--r-- | gcc-4.4.3/libstdc++-v3/doc/html/manual/pairs.html | 42 |
1 files changed, 0 insertions, 42 deletions
diff --git a/gcc-4.4.3/libstdc++-v3/doc/html/manual/pairs.html b/gcc-4.4.3/libstdc++-v3/doc/html/manual/pairs.html deleted file mode 100644 index 608344cfb..000000000 --- a/gcc-4.4.3/libstdc++-v3/doc/html/manual/pairs.html +++ /dev/null @@ -1,42 +0,0 @@ -<?xml version="1.0" encoding="UTF-8" standalone="no"?> -<!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"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><title>Chapter 10. Pairs</title><meta name="generator" content="DocBook XSL Stylesheets V1.74.0" /><meta name="keywords" content=" ISO C++ , library " /><link rel="home" href="../spine.html" title="The GNU C++ Library Documentation" /><link rel="up" href="utilities.html" title="Part IV. Utilities" /><link rel="prev" href="functors.html" title="Chapter 9. Functors" /><link rel="next" href="memory.html" title="Chapter 11. Memory" /></head><body><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">Chapter 10. Pairs</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="functors.html">Prev</a> </td><th width="60%" align="center">Part IV. - Utilities - -</th><td width="20%" align="right"> <a accesskey="n" href="memory.html">Next</a></td></tr></table><hr /></div><div class="chapter" lang="en" xml:lang="en"><div class="titlepage"><div><div><h2 class="title"><a id="manual.util.pairs"></a>Chapter 10. Pairs</h2></div></div></div><p>The <code class="code">pair<T1,T2></code> is a simple and handy way to - carry around a pair of objects. One is of type T1, and another of - type T2; they may be the same type, but you don't get anything - extra if they are. The two members can be accessed directly, as - <code class="code">.first</code> and <code class="code">.second</code>. - </p><p>Construction is simple. The default ctor initializes each member - with its respective default ctor. The other simple ctor, - </p><pre class="programlisting"> - pair (const T1& x, const T2& y); - </pre><p>does what you think it does, <code class="code">first</code> getting <code class="code">x</code> - and <code class="code">second</code> getting <code class="code">y</code>. - </p><p>There is a copy constructor, but it requires that your compiler - handle member function templates: - </p><pre class="programlisting"> - template <class U, class V> pair (const pair<U,V>& p); - </pre><p>The compiler will convert as necessary from U to T1 and from - V to T2 in order to perform the respective initializations. - </p><p>The comparison operators are done for you. Equality - of two <code class="code">pair<T1,T2></code>s is defined as both <code class="code">first</code> - members comparing equal and both <code class="code">second</code> members comparing - equal; this simply delegates responsibility to the respective - <code class="code">operator==</code> functions (for types like MyClass) or builtin - comparisons (for types like int, char, etc). - </p><p> - The less-than operator is a bit odd the first time you see it. It - is defined as evaluating to: - </p><pre class="programlisting"> - x.first < y.first || - ( !(y.first < x.first) && x.second < y.second ) - </pre><p>The other operators are not defined using the <code class="code">rel_ops</code> - functions above, but their semantics are the same. - </p><p>Finally, there is a template function called <code class="function">make_pair</code> - that takes two references-to-const objects and returns an - instance of a pair instantiated on their respective types: - </p><pre class="programlisting"> - pair<int,MyClass> p = make_pair(4,myobject); - </pre></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="functors.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="utilities.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="memory.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">Chapter 9. Functors </td><td width="20%" align="center"><a accesskey="h" href="../spine.html">Home</a></td><td width="40%" align="right" valign="top"> Chapter 11. Memory</td></tr></table></div></body></html> |