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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2//EN">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Boost.Range Utilities </title>
<link rel="stylesheet" href="style.css" type="text/css">
</head>
<body>
<table border="0" >
<tr>
<td ><img src="../../../boost.png" border="0" ></td>
<td ><h1 align="center">Boost.Range</h1></td>
</tr>
</table>
<h2>Utilities</h2>
<p>
Having an abstraction that encapsulates a pair of iterators is very useful. The
standard library uses <code>std::pair</code> in some circumstances, but that
class is cumbersome to use because we need to specify two template arguments,
and for all range algorithm purposes we must enforce the two template arguments
to be the same. Moreover, <code>std::pair<iterator,iterator></code> is hardly
self-documenting whereas more domain specific class names are. Therefore these
two classes are provided:
<ul>
<li>
Class <a href=#iter_range><code>iterator_range</code></a>
<li>
Class <a href=#sub_range><code>sub_range</code></a>
</ul>
</ul>
The <code>iterator_range</code> class is templated on an
<a href="../../iterator/doc/new-iter-concepts.html#forward-traversal-iterators-lib-forward-traversal-iterators">Forward
Traversal Iterator</a> and should be used whenever fairly general code is needed.
The <code>sub_range</code> class is templated on an <a href="range.html#forward_range">Forward
Range</a> and it is less general, but a bit easier to use since its template
argument is easier to specify. The biggest difference is, however, that a
<code>sub_range</code> can propagate constness because it knows what a
corresponding <code>const_iterator</code> is. </p>
<p>
Both classes can be used as ranges since they implement the <a
href="boost_range.html#minimal_interface">minimal interface</a>
required for this to work automatically.
</p>
<hr>
<a name=iter_range></a> <h1>Class <code>iterator_range</code></h1>
<p>
The intention of the <code>iterator_range</code> class is to encapsulate two
iterators so they fulfill the <a
href="range.html#forward_range">Forward Range</a> concept. A few other
functions are also provided for convenience.
</p>
<p>
If the template argument is not a model of Forward Traversal Iterator, one can
still use a subset of the interface. In particular, <code>size()</code> requires
Forward Traversal Iterators whereas <code>empty()</code> only requires Single
Pass Iterators.
</p>
<p>
Recall that many default constructed iterators
are <i>singular</i> and hence can only be assigned, but not compared or
incremented or anything. However, if one creates a default constructed
<code>iterator_range</code>, then one
can still call all its member functions. This means that the
<code>iterator_range</code> will still be usable in many contexts even
though the iterators underneath are not.
</p>
<h3>Synopsis</h3>
<pre>
<span class=keyword>namespace </span><span class=identifier>boost</span>
<span class=special>{
</span><span class=keyword>template</span><span class=special>< </span><span class=keyword>class </span><span class=identifier>ForwardTraversalIterator </span><span class=special>>
</span><span class=keyword>class </span><span class=identifier>iterator_range
</span><span class=special>{
</span><span class=keyword>public</span><span class=special>: </span><span class=comment>// Forward Range types
</span><span class=keyword>typedef </span><span class=special>... </span><span class=identifier>value_type</span><span class=special>;
</span><span class=keyword>typedef </span><span class=special>... </span><span class=identifier>difference_type</span><span class=special>;
</span><span class=keyword>typedef </span><span class=special>... </span><span class=identifier>size_type</span><span class=special>;
</span><span class=keyword>typedef </span><span class=identifier>ForwardTraversalIterator </span><span class=identifier>iterator</span><span class=special>;
</span><span class=keyword>typedef </span><span class=identifier>ForwardTraversalIterator </span><span class=identifier>const_iterator</span><span class=special>;
</span><span class=keyword>public</span><span class=special>: </span><span class=comment>// construction, assignment
</span><span class=keyword>template</span><span class=special>< </span><span class=keyword>class </span><span class=identifier>ForwardTraversalIterator2 </span><span class=special>>
</span><span class=identifier>iterator_range</span><span class=special>( </span><span class=identifier>ForwardTraversalIterator2 </span><span class=identifier>Begin</span><span class=special>, </span><span class=identifier>ForwardTraversalIterator2 </span><span class=identifier>End </span><span class=special>);
</span><span class=keyword>template</span><span class=special>< </span><span class=keyword>class </span><span class=identifier>ForwardRange </span><span class=special>>
</span><span class=identifier>iterator_range</span><span class=special>( </span><span class=identifier>ForwardRange</span><span class=special>& </span><span class=identifier>r </span><span class=special>);
</span><span class=keyword>template</span><span class=special>< </span><span class=keyword>class </span><span class=identifier>ForwardRange </span><span class=special>>
</span><span class=identifier>iterator_range</span><span class=special>( </span><span class=keyword>const </span><span class=identifier>ForwardRange</span><span class=special>& </span><span class=identifier>r </span><span class=special>);
</span><span class=keyword>template</span><span class=special>< </span><span class=keyword>class </span><span class=identifier>ForwardRange </span><span class=special>>
</span><span class=identifier>iterator_range</span><span class=special>& </span><span class=keyword>operator</span><span class=special>=( </span><span class=identifier>ForwardRange</span><span class=special>& </span><span class=identifier>r </span><span class=special>);
</span><span class=keyword>template</span><span class=special>< </span><span class=keyword>class </span><span class=identifier>ForwardRange </span><span class=special>>
</span><span class=identifier>iterator_range</span><span class=special>& </span><span class=keyword>operator</span><span class=special>=( </span><span class=keyword>const </span><span class=identifier>ForwardRange</span><span class=special>& </span><span class=identifier>r </span><span class=special>);
</span><span class=keyword>public</span><span class=special>: </span><span class=comment>// Forward Range functions
</span><span class=identifier>iterator </span><span class=identifier>begin</span><span class=special>() </span><span class=keyword>const</span><span class=special>;
</span><span class=identifier>iterator </span><span class=identifier>end</span><span class=special>() </span><span class=keyword>const</span><span class=special>;
</span><span class=identifier>size_type </span><span class=identifier>size</span><span class=special>() </span><span class=keyword>const</span><span class=special>;
</span><span class=keyword>bool </span><span class=identifier>empty</span><span class=special>() </span><span class=keyword>const</span><span class=special>;
</span><span class=keyword>public</span><span class=special>: </span><span class=comment>// convenience
</span><span class=keyword>operator </span><a
href="#unspecified_bool"><span class=identifier>unspecified_bool_type</span></a><span class=special>() </span><span class=keyword>const</span><span class=special>;
</span> <span class=keyword>bool</span> <span
class=identifier><a href="#equal">equal</a></span><span
class=special>( </span><span class=keyword>const <span
class=identifier>iterator_range</span><span class=special>& ) </span><span
class=keyword>const;</span>
</span><span class=special>};
</span><span class=comment>// stream output
</span><span class=keyword>template</span><span class=special>< </span><span class=keyword>class </span><span class=identifier>ForwardTraversalIterator</span><span class=special>, </span><span class=keyword>class </span><span class=identifier>T</span><span class=special>, </span><span class=keyword>class </span><span class=identifier>Traits </span><span class=special>>
</span><span class=identifier>std</span><span class=special>::</span><span class=identifier>basic_ostream</span><span class=special><</span><span class=identifier>T</span><span class=special>,</span><span class=identifier>Traits</span><span class=special>>&
</span><span class=keyword>operator</span><span class=special><<( </span><span class=identifier>std</span><span class=special>::</span><span class=identifier>basic_ostream</span><span class=special><</span><span class=identifier>T</span><span class=special>,</span><span class=identifier>Traits</span><span class=special>>& </span><span class=identifier>Os</span><span class=special>,
</span><span class=keyword>const </span><span class=identifier>iterator_range</span><span class=special><</span><span class=identifier>ForwardTraversalIterator</span><span class=special>>& </span><span class=identifier>r </span><span class=special>);
</span><span class=comment>// <a href="#comparison">comparison</a>
</span><span class=keyword>template</span><span class=special>< </span><span class=keyword>class </span><span class=identifier>ForwardTraversalIterator</span><span class=special>, </span><span class=keyword>class </span><span class=identifier>ForwardTraversalIterator2 </span><span class=special>>
</span><span class=keyword>bool </span><span class=keyword>operator</span><span class=special>==( </span><span class=keyword>const </span><span class=identifier>iterator_range</span><span class=special><</span><span class=identifier>ForwardTraversalIterator</span><span class=special>>& </span><span class=identifier>l</span><span class=special>,
</span><span class=keyword>const </span><span class=identifier>iterator_range</span><span class=special><</span><span class=identifier>ForwardTraversalIterator2</span><span class=special>>& </span><span class=identifier>r </span><span class=special>);
</span><span class=keyword>template</span><span class=special>< </span><span class=keyword>class </span><span class=identifier>ForwardTraversalIterator</span><span class=special>, </span><span class=keyword>class </span><span class=identifier>ForwardRange </span><span class=special>>
</span><span class=keyword>bool </span><span class=keyword>operator</span><span class=special>==( </span><span class=keyword>const </span><span class=identifier>iterator_range</span><span class=special><</span><span class=identifier>ForwardTraversalIterator</span><span class=special>>& </span><span class=identifier>l</span><span class=special>,
</span><span class=keyword>const </span><span class=identifier>ForwardRange</span><span class=special>& </span><span class=identifier>r </span><span class=special>);
</span><span class=keyword>template</span><span class=special>< </span><span class=keyword>class </span><span class=identifier>ForwardTraversalIterator</span><span class=special>, </span><span class=keyword>class </span><span class=identifier>ForwardRange </span><span class=special>>
</span><span class=keyword>bool </span><span class=keyword>operator</span><span class=special>==( </span><span class=keyword>const </span><span class=identifier>ForwardRange</span><span class=special>& </span><span class=identifier>l</span><span class=special>,
</span><span class=keyword>const </span><span class=identifier>iterator_range</span><span class=special><</span><span class=identifier>ForwardTraversalIterator</span><span class=special>>& </span><span class=identifier>r </span><span class=special>);
</span><span class=keyword>template</span><span class=special>< </span><span class=keyword>class </span><span class=identifier>ForwardTraversalIterator</span><span class=special>, </span><span class=keyword>class </span><span class=identifier>ForwardTraversalIterator2 </span><span class=special>>
</span><span class=keyword>bool </span><span class=keyword>operator</span><span class=special>!=( </span><span class=keyword>const </span><span class=identifier>iterator_range</span><span class=special><</span><span class=identifier>ForwardTraversalIterator</span><span class=special>>& </span><span class=identifier>l</span><span class=special>,
</span><span class=keyword>const </span><span class=identifier>iterator_range</span><span class=special><</span><span class=identifier>ForwardTraversalIterator2</span><span class=special>>& </span><span class=identifier>r </span><span class=special>);
</span><span class=keyword>template</span><span class=special>< </span><span class=keyword>class </span><span class=identifier>ForwardTraversalIterator</span><span class=special>, </span><span class=keyword>class </span><span class=identifier>ForwardRange </span><span class=special>>
</span><span class=keyword>bool </span><span class=keyword>operator</span><span class=special>!=( </span><span class=keyword>const </span><span class=identifier>iterator_range</span><span class=special><</span><span class=identifier>ForwardTraversalIterator</span><span class=special>>& </span><span class=identifier>l</span><span class=special>,
</span><span class=keyword>const </span><span class=identifier>ForwardRange</span><span class=special>& </span><span class=identifier>r </span><span class=special>);
</span><span class=keyword>template</span><span class=special>< </span><span class=keyword>class </span><span class=identifier>ForwardTraversalIterator</span><span class=special>, </span><span class=keyword>class </span><span class=identifier>ForwardRange </span><span class=special>>
</span><span class=keyword>bool </span><span class=keyword>operator</span><span class=special>!=( </span><span class=keyword>const </span><span class=identifier>ForwardRange</span><span class=special>& </span><span class=identifier>l</span><span class=special>,
</span><span class=keyword>const </span><span class=identifier>iterator_range</span><span class=special><</span><span class=identifier>ForwardTraversalIterator</span><span class=special>>& </span><span class=identifier>r </span><span class=special>);
</span><span class=keyword>template</span><span class=special>< </span><span class=keyword>class </span><span class=identifier>ForwardTraversalIterator</span><span class=special>, </span><span class=keyword>class </span><span class=identifier>ForwardTraversalIterator2 </span><span class=special>>
</span><span class=keyword>bool </span><span class=keyword>operator</span><span class=special><( </span><span class=keyword>const </span><span class=identifier>iterator_range</span><span class=special><</span><span class=identifier>ForwardTraversalIterator</span><span class=special>>& </span><span class=identifier>l</span><span class=special>,
</span><span class=keyword>const </span><span class=identifier>iterator_range</span><span class=special><</span><span class=identifier>ForwardTraversalIterator2</span><span class=special>>& </span><span class=identifier>r </span><span class=special>);
</span><span class=keyword>template</span><span class=special>< </span><span class=keyword>class </span><span class=identifier>ForwardTraversalIterator</span><span class=special>, </span><span class=keyword>class </span><span class=identifier>ForwardRange </span><span class=special>>
</span><span class=keyword>bool </span><span class=keyword>operator</span><span class=special><( </span><span class=keyword>const </span><span class=identifier>iterator_range</span><span class=special><</span><span class=identifier>ForwardTraversalIterator</span><span class=special>>& </span><span class=identifier>l</span><span class=special>,
</span><span class=keyword>const </span><span class=identifier>ForwardRange</span><span class=special>& </span><span class=identifier>r </span><span class=special>);
</span><span class=keyword>template</span><span class=special>< </span><span class=keyword>class </span><span class=identifier>ForwardTraversalIterator</span><span class=special>, </span><span class=keyword>class </span><span class=identifier>ForwardRange </span><span class=special>>
</span><span class=keyword>bool </span><span class=keyword>operator</span><span class=special><( </span><span class=keyword>const </span><span class=identifier>ForwardRange</span><span class=special>& </span><span class=identifier>l</span><span class=special>,
</span><span class=keyword>const </span><span class=identifier>iterator_range</span><span class=special><</span><span class=identifier>ForwardTraversalIterator</span><span class=special>>& </span><span class=identifier>r </span><span class=special>);</span>
</span><span class=comment>// external construction
</span><span class=keyword>template</span><span class=special>< </span><span class=keyword>class </span><span class=identifier>ForwardTraversalIterator </span><span class=special>>
</span><span class=identifier>iterator_range</span><span class=special>< </span><span class=identifier>ForwardTraversalIterator </span><span class=special>>
</span><span class=identifier>make_iterator_range</span><span class=special>( </span><span class=identifier>ForwardTraversalIterator </span><span class=identifier>Begin</span><span class=special>,
</span><span class=identifier>ForwardTraversalIterator </span><span class=identifier>End </span><span class=special>);
</span><span class=keyword>template</span><span class=special>< </span><span class=keyword>class </span><span class=identifier>ForwardRange </span><span class=special>>
</span><span class=identifier>iterator_range</span><span class=special>< </span><span class=keyword>typename </span><span class=identifier>iterator_of</span><span class=special><</span><span class=identifier>ForwardRange</span><span class=special>>::</span><span class=identifier>type </span><span class=special>>
</span><span class=identifier>make_iterator_range</span><span class=special>( </span><span class=identifier>ForwardRange</span><span class=special>& </span><span class=identifier>r </span><span class=special>);
</span><span class=keyword>template</span><span class=special>< </span><span class=keyword>class </span><span class=identifier>ForwardRange </span><span class=special>>
</span><span class=identifier>iterator_range</span><span class=special>< </span><span class=keyword>typename </span><span class=identifier>const_iterator_of</span><span class=special><</span><span class=identifier>ForwardRange</span><span class=special>>::</span><span class=identifier>type </span><span class=special>>
</span><span class=identifier>make_iterator_range</span><span class=special>( </span><span class=keyword>const </span><span class=identifier>ForwardRange</span><span class=special>& </span><span class=identifier>r </span><span class=special>);
</span><span class=comment>// convenience
</span><span class=keyword>template</span><span class=special>< </span><span class=keyword>class </span><span class=identifier>Sequence</span><span class=special>, </span><span class=keyword>class </span><span class=identifier>ForwardRange </span><span class=special>>
</span><span class=identifier>Sequence </span><a href="#copy_range"><span
class=identifier>copy_range</span></a><span class=special>( </span><span
class=keyword>const </span><span class=identifier>ForwardRange</span><span class=special>& </span><span class=identifier>r </span><span class=special>);
</span><span class=keyword>template</span><span class=special>< </span><span class=keyword>class </span><span class=identifier>Sequence</span><span class=special>, </span><span class=keyword>class </span><span class=identifier>ForwardRange</span><span class=special>, </span><span class=keyword>class </span><span class=identifier>Func </span><span class=special>>
</span><span class=identifier>Sequence </span><a
href="#transform_range"><span
class=identifier>transform_range</span></a><span class=special>( </span><span
class=keyword>const </span><span class=identifier>ForwardRange</span><span class=special>& </span><span class=identifier>r</span><span class=special>, </span><span class=identifier>Func </span><span class=identifier>func </span><span class=special>);
</span>
<span class=special>} </span><span class=comment>// namespace 'boost'</span>
</pre>
<p>
If an instance of
<code>iterator_range</code> is constructed by a client with two iterators, the
client must ensure that the two iterators delimit a valid closed-open range
<code>[begin,end)</code>.
</p>
<p>
It is worth noticing that the templated constructors and assignment operators
allow conversion from <code>iterator_range<iterator></code> to
<code>iterator_range<const_iterator></code>. Similarly, since the comparison
operators have two template arguments, we can compare ranges whenever the
iterators are comparable; for example when we are dealing with const and
non-const iterators from the same container. </p>
<h3>Details member functions</h3>
<p>
<a name="unspecified_bool"></a>
<code>operator unspecified_bool_type() const; </code>
<blockquote>
<i>Returns</i> <code>!empty();</code>
</blockquote>
</p>
<p>
<a name="equal"></a>
<code>bool equal( iterator_range& r ) const;</code>
<blockquote>
<i>Returns</i> <code>begin() == r.begin() && end() == r.end();</code>
</blockquote>
</p>
<h3>Details functions</h3>
<p>
<a name="comparison"></a>
<code>bool operator==( const ForwardRange1& l, const ForwardRange2& r );</code>
<blockquote>
<i>Returns</i> <code>size(l) != size(r) ? false : std::equal( begin(l), end(l), begin(r) );</code> </blockquote> </p>
<code>bool operator!=( const ForwardRange1& l, const ForwardRange2& r );</code>
<blockquote>
<i>Returns</i> <code>!( l == r );</code>
</blockquote>
<code>bool operator<( const ForwardRange1& l, const ForwardRange2& r );</code>
<blockquote>
<i>Returns</i> <code>std::lexicographical_compare( begin(l), end(l), begin(r), end(r) );</code> </blockquote>
<p>
<a name="copy_range"></a>
<code>Sequence copy_range( const ForwardRange& r );</code>
<blockquote>
<i>Returns</i> <code>Sequence( begin(r), end(r) );</code>
</blockquote>
</p>
<p>
<a name="transform_range"></a>
<code>Sequence transform_range( const ForwardRange& r, Func func );</code>
<blockquote>
<i>Effects</i> <br>
<code>Sequence seq;</code> <br>
<code>std::transform( begin(r), end(r), std::back_inserter(seq), func );</code>
<br>
<code>return seq;</code>
</blockquote>
</p>
<hr> <a name=sub_range></a>
<h1>Class <code>sub_range</code></h1>
The <code>sub_range</code> class inherits all its functionality
from the <a href="#iter_range"><code>iterator_range</code></a> class.
The <code>sub_range</code> class is often easier to use because
one must specify the <a href="range.html#forward_range">Forward Range</a>
template argument instead of an iterator. Moreover, the <code>sub_range</code>
class can propagate constness since it knows what a corresponding
<code>const_iterator</code> is.
<h3>Synopsis</h3>
<pre>
<span class=keyword>namespace </span><span class=identifier>boost</span>
<span class=special>{
</span><span class=keyword>template</span><span class=special>< </span><span class=keyword>class </span><span class=identifier>ForwardRange </span><span class=special>>
</span><span class=keyword>class </span><span class=identifier>sub_range </span><span class=special>: </span><span class=keyword>public </span><span class=identifier>iterator_range</span><span class=special>< </span><span class=keyword>typename </span><span class=identifier>range_result_iterator</span><span class=special><</span><span class=identifier>ForwardRange</span><span class=special>>::</span><span class=identifier>type </span><span class=special>>
</span><span class=special>{
</span><span class=keyword>public</span><span class=special>: </span>
<span class=keyword>typedef </span><span class=keyword>typename </span><span class=identifier>range_result_iterator</span><span class=special><</span><span class=identifier>ForwardRange</span><spanclass=special>>::</span><span class=identifier>type </span><span class=identifier>iterator</span><span class=special>;</span>
<span class=keyword>typedef </span><span class=keyword>typename </span><span class=identifier>range_const_iterator</span><span class=special><</span><span class=identifier>ForwardRange</span><span class=special>>::</span><span class=identifier>type </span><span class=identifier>const_iterator</span><span class=special>;</span>
<span class=keyword>public</span><span class=special>: </span><span class=comment>// construction, assignment
</span><span class=keyword>template</span><span class=special>< </span><span class=keyword>class </span><span class=identifier>ForwardTraversalIterator </span><span class=special>>
</span><span class=identifier>sub_range</span><span class=special>( </span><span class=identifier>ForwardTraversalIterator </span><span class=identifier>Begin</span><span class=special>, </span><span class=identifier>ForwardTraversalIterator </span><span class=identifier>End </span><span class=special>);
</span><span class=keyword>template</span><span class=special>< </span><span class=keyword>class </span><span class=identifier>ForwardRange2 </span><span class=special>>
</span><span class=identifier>sub_range</span><span class=special>( </span><span class=identifier>ForwardRange2</span><span class=special>& </span><span class=identifier>r </span><span class=special>);
</span><span class=keyword>template</span><span class=special>< </span><span class=keyword>class </span><span class=identifier>ForwardRange2 </span><span class=special>>
</span><span class=identifier>sub_range</span><span class=special>( </span><span class=keyword>const </span><span class=identifier>Range2</span><span class=special>& </span><span class=identifier>r </span><span class=special>);
</span><span class=keyword>template</span><span class=special>< </span><span class=keyword>class </span><span class=identifier>ForwardRange2 </span><span class=special>>
</span><span class=identifier>sub_range</span><span class=special>& </span><span class=keyword>operator</span><span class=special>=( </span><span class=identifier>ForwardRange2</span><span class=special>& </span><span class=identifier>r </span><span class=special>);
</span><span class=keyword>template</span><span class=special>< </span><span class=keyword>class </span><span class=identifier>ForwardRange2 </span><span class=special>>
</span><span class=identifier>sub_range</span><span class=special>& </span><span class=keyword>operator</span><span class=special>=( </span><span class=keyword>const </span><span class=identifier>ForwardRange2</span><span class=special>& </span><span class=identifier>r </span><span class=special>);
</span>
<span class=keyword>public</span><span class=special>:
</span><span class=identifier>iterator </span><span
class=identifier>begin</span><span class=special>();
</span><span class=identifier>const_iterator </span><span class=identifier>begin</span><span class=special>() </span><span class=keyword>const</span><span class=special>;
</span><span class=identifier>iterator </span><span class=identifier>end</span><span class=special>();
</span><span class=identifier>const_iterator </span><span class=identifier>end</span><span class=special>() </span><span class=keyword>const</span><span class=special>;</span>
<span class=keyword>public</span><span class=special>:
</span><span class=comment>// rest of interface inherited from iterator_range
</span><span class=special>};
</span>
<span class=special>} </span><span class=comment>// namespace 'boost'</span>
</pre>
<p>
The class should be trivial to use as seen below.
Imagine that we have an algorithm that searches for a sub-string in a string.
The
result is an <code>iterator_range</code>, that delimits the match. We need to
store the result
from this algorithm. Here is an example of how we can do it with and without
<code>sub_range</code>
<pre>
<span class=identifier>std</span><span class=special>::</span><span class=identifier>string </span><span class=identifier>str</span><span class=special>(</span><span class=string>"hello"</span><span class=special>);
</span><span class=identifier>iterator_range</span><span class=special><</span><span class=identifier>std</span><span class=special>::</span><span class=identifier>string</span><span class=special>::</span><span class=identifier>iterator</span><span class=special>> </span><span class=identifier>ir </span><span class=special>= </span><span class=identifier>find_first</span><span class=special>( </span><span class=identifier>str</span><span class=special>, </span><span class=string>"ll" </span><span class=special>);
</span><span class=identifier>sub_range</span><span class=special><</span><span class=identifier>std</span><span class=special>::</span><span class=identifier>string</span><span class=special>> </span><span class=identifier>sub </span><span class=special>= </span><span class=identifier>find_first</span><span class=special>( </span><span class=identifier>str</span><span class=special>, </span><span class=string>"ll" </span><span class=special>);</span>
</pre>
</p>
<hr>
<p>
(C) Copyright Thorsten Ottosen 2003-2004
</p>
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