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Added cross-reference; improved policies documentation

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[SVN r9286]
This commit is contained in:
Dave Abrahams 2001-02-20 03:49:26 +00:00
parent 168012b465
commit 78886ab383
1 changed files with 37 additions and 5 deletions
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iterator_adaptors.htm
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@ -210,11 +210,14 @@ struct iterator_adaptor;
"http://www.sgi.com/tech/stl/RandomAccessIterator.html">Random Access
Iterator</a>. Your <tt>Policies</tt> class must implement three, four, or
seven of the core iterator operations below depending on the iterator
categories you want it to support.
categories you want it to support.<br>
<br>
<table border="1" summary="iterator_adaptor Policies operations">
<caption>
<b>Core Iterator Operations</b>
<b>Core Iterator Operations</b><br>
<tt>T</tt>: iterator type; <tt>p</tt>: object of type T; <tt>n</tt>: <tt>T::size_type</tt>; <tt>x</tt>: <tt>T::difference_type</tt>; <tt>p1</tt>, <tt>p2</tt>: iterators
</caption>
<tr>
@ -222,12 +225,16 @@ struct iterator_adaptor;
<th>Effects
<th>Implements Operations
<th>Required for Iterator Categories
<tr>
<td><tt>dereference</tt>
<td>returns an element of the iterator's <tt>reference</tt> type
<td><tt>*p</tt>, <tt>p[n]</tt>
<td rowspan="3"><a href=
"http://www.sgi.com/tech/stl/InputIterator.html">Input</a>/ <a href=
@ -243,16 +250,22 @@ struct iterator_adaptor;
<td>tests the iterator for equality
<td><tt>p1&nbsp;==&nbsp;p2</tt>, <tt>p1&nbsp;!=&nbsp;p2</tt>
<tr>
<td><tt>increment</tt>
<td>increments the iterator
<td><tt>++p</tt>, <tt>p++</tt>
<tr>
<td><tt>decrement</tt>
<td>decrements the iterator
<td><tt>--p</tt>, <tt>p--</tt>
<td><a href=
"http://www.sgi.com/tech/stl/BidirectionalIterator.html">Bidirectional</a>/
<a href="http://www.sgi.com/tech/stl/RandomAccessIterator.html">Random
@ -263,7 +276,13 @@ struct iterator_adaptor;
<td>imposes a <a href=
"http://www.sgi.com/tech/stl/StrictWeakOrdering.html">Strict Weak
Ordering</a> relation on the iterator's <tt>reference</tt> type
Ordering</a> relation on iterators
<td>
<tt>p1&nbsp;&lt;&nbsp;p2</tt>,
<tt>p1&nbsp;&lt;=&nbsp;p2</tt>,
<tt>p1&nbsp;&gt;&nbsp;p2</tt>,
<tt>p1&nbsp;&gt;=&nbsp;p2</tt>
<td rowspan="3"><a href=
"http://www.sgi.com/tech/stl/RandomAccessIterator.html">Random
@ -274,10 +293,20 @@ struct iterator_adaptor;
<td>measures the distance between iterators
<td><tt>p1 - p2</tt>
<tr>
<td><tt>advance</tt>
<td>adds an integer offset to iterators
<td>
<tt>p&nbsp;+&nbsp;x</tt>,
<tt>x&nbsp;+&nbsp;p</tt>,
<tt>p&nbsp;+=&nbsp;x</tt>,
<tt>p&nbsp;-&nbsp;x</tt>,
<tt>p&nbsp;-=&nbsp;x</tt>
</table>
<p>The library also supplies a "trivial" policy class,
@ -516,8 +545,11 @@ int main(int, char*[])
<li><tt>const</tt> and non-<tt>const</tt> pointers to <tt>T</tt> can be
freely subtracted, in any order.
</ul>
Getting user-defined iterators to work together that way is nontrivial, but
<tt>iterator_adaptor</tt> can make it easy. The rules are as follows:
Getting user-defined iterators to work together that way is nontrivial (see
<a href="reverse_iterator.htm#interactions">here</a> for an example of where
the C++ standard got it wrong), but <tt>iterator_adaptor</tt> can make it
easy. The rules are as follows:
<ul>
<li><a name="interoperable">Adapted iterators that share the same <tt>Policies</tt>,